Ankersrum USA

Mushroom Walnut Burgers

In the bonus post for this month (subscribe to receive!) I was talking about all the great attachments that come with the Meat Mincer Complete package that have nothing to do with grinding meat or making sausages.  It got me thinking about ways to make this attachment appealing to someone that doesn’t eat a lot of meat, like me.  So then I was determined to make a vegetarian burger using the meat grinder.  Sacrilegious, I know.  But the former vegetarian in me got a laugh out of it.  Now, I have nothing against eating meat and use the grinder all the time for tasty burgers, meatballs, etc.  It is an awesome meat grinder, but it also makes a pretty fabulous mushroom burger too.

While there are umpteenth fake meat substitutes at the grocery store, they kinda weird me out.  Have you ever read the ingredient list on some of those?!  I mean, how much has that poor soybean been processed to now somehow resemble ground meat?  Mushrooms have long been used by vegetarians to mimic the texture of meat, and I figured why can’t I run them through the grinder to resemble ground meat and make a burger out of it?  Large portabellas were the obvious choice to begin my mushroom burger quest.  While I knew mushrooms released a lot of liquid when cooked, I was a little alarmed and surprised by how wet and unappealing my first round of burger testing was.  So I tweaked it a couple times and learned that roasting the mushrooms on a rack and then squeezing them out afterwards was key, as well as catching the mushrooms in a strainer as they were grinding to get rid of any remaining liquid.

Almost 2 cups of liquid came out of these mushrooms – save the mushroom “broth” to use in soups, stews or cooking grains/beans in.


However, even after all that I kept having about a half cup of mushrooms get left behind in the grinder.  They were just limply hanging out, refusing to come through.  Now I was already using a little bit of dry breadcrumbs to bind the burgers together, and as I was trying to figure out what to do with the stubborn mushrooms in the grinder, my eyes glanced at a bag of rolls on my kitchen counter and I tore one up and fed it through the machine.  Voila!  Mushrooms out and some fresh breadcrumbs to boot!  For the finished recipe I found that a sturdy bread, like a sourdough or ciabatta, worked best for feeding through the grinder.  Softer bread gums up a bit.  If you are gluten free, just substitute a slice of your favorite gluten free bread.

L: you can see already more liquid collecting at bottom. R: bread ground through to force last bit of mushrooms out.
After mushrooms and bread are ground, push down gently on mixture in strainer to remove any excess liquid. Mushrooms should look like above when done.


While roasted mushrooms are delicious, they don’t offer a lot of protein.  And if I was going to go through the trouble of figuring out a vegetarian burger, I wanted it to be a viable dinner option.  Enter walnuts, and the use of the nut grater, also included in the Meat Mincer Complete package.  This attachment is pretty amazing.  I hadn’t used it much until last month, and now I am on fresh nut meal kick.  I chose walnuts because, well, I had a lot of them in the freezer and they pair nicely with mushrooms.  I toasted the walnuts for a deeper nutty roasted flavor, which I figured would be ideal for a meat free burger.  You can roast the mushrooms and nuts at the same time in the oven.  Just make sure to use the attachment FIRST for grating the nuts and then for grinding mushrooms.  If you grate nuts first you don’t have to wash any of the components that you use again for grinding.  But the mushrooms leave behind a little moisture in the grinder that makes grating nuts afterwards a pain.  Pecans make a nice substitute if you aren’t a walnut fan.  A quick tip on the nut grater, make sure to use the splash guard!!  I didn’t the first time and flung nut meal all over my kitchen counter and floor.

Freshly ground toasted walnuts make the house smell amazing!


A couple eggs added more protein and helped bind the ingredients together.  Worcestershire sauce and soy sauce helped add even more meaty flavor, and a few other spices and herbs rounded out the recipe.

Just enough liquid to hold it all together.


I haven’t tried these on the grill, and would recommend using a grill pan because I’m not sure if they would hold together enough on just a grill grate.  But they cook up quickly on a griddle or large skillet on the stovetop.


I treated these just like a meat burger when serving them to my family and had buns and all the toppings and condiments that usually go with hamburgers.  My meat loving husband gave a thumbs up.  If you have a little extra time you could even make homemade buns like these with potato flour or these which show you how to turn regular (and gluten-free!) bread dough into hamburger buns.


If you want a visual refresher on how to put together all the attachments for the Meat Mincer Complete, check out this video.  Thanks for reading, hope you enjoy the recipe and, once again, please let us know if you have any questions or comments!


Mushroom Walnut Burgers

Prep Time: 35 minutes

Cook Time: 41 minutes (total)


3 1/2 oz. walnuts

8 large portabella caps

olive oil

1 slice sourdough or artisanal bread, toasted

1/4 cup finely chopped green onion

2 large cloves garlic, minced

2 eggs

1/2 tsp. dry mustard

freshly ground black pepper, to taste

1/2 tsp. kosher salt

2 tsp. Worcestershire sauce

1 tsp. reduced sodium soy sauce

1-2 Tbsp. dry bread crumbs

Additional/optional: hamburger buns, condiments and toppings


Preheat oven to 400° F.  Spread walnuts out on a half sheet pan or cookie sheet and toast for 8-10 minutes or until beginning to brown.  Set aside to cool.

Set a cooling rack in a half sheet pan.  Brush any dirt off mushroom caps and remove stems.  Place stem side down on the rack and lightly oil the tops with olive oil.  Roast in a 400º oven for 25 minutes.  Once cool enough to handle, fold in half and squeeze out excess liquid.  Place in the freezer until cold to the touch, approximately 20 minutes.

Set up the Ankarsrum base with the nut grater attachment.  Place a medium bowl underneath to catch the freshly ground nut meal.  Once walnuts are cool, run through the nut grater on the lowest speed, using the plunger to feed them through.  You should have 1 cup nut meal.

Set up the Ankarsrum base with the meat grinder attachment and the 6 mm disc.  Place a large bowl underneath with a strainer to catch the freshly ground mushrooms.  Cut the portabellas in half and feed through the grinder on medium speed (3 o’clock).  Once all the mushrooms are ground, tear the slice of sourdough toast into pieces that will fit through the top of the grinder and use the plunger to push them through.

Gently press on the ground mushrooms/breadcrumbs in the strainer to remove any remaining liquid.  Transfer to a large bowl.  Add remaining ingredients except dry bread crumbs.  Mix together thoroughly.  Add 1 tablespoon dry breadcrumbs and if mixture still seems a little wet add remaining tablespoon.  Mix until combined.

Preheat a nonstick flat griddle or large skillet over medium heat.  Divide the mushroom mixture into 6 equal portions and form into a burger shape.  Cook for 3-4 minutes on one side, until browned, and then carefully flip and cook another 3-4 minutes on other side.

Serve immediately with buns, condiments and toppings.


Yield: 6 servings

For Whole Grain:

-Replace slice of sourdough with whole wheat sourdough

-Replace dry breadcrumbs with an equal amount of whole wheat dry breadcrumbs

For Gluten-Free:

-Replace slice of sourdough with slice of favorite gluten-free bread

-Replace dry breadcrumbs with equal amount gluten-free dry breadcrumbs

-Use equal amount of gluten-free soy sauce, such as San-J Tamari Gluten Free Soy Sauce








Published by

Carmi Adams

Carmi Adams has loved cooking from a very early age; requesting fondue pots and cookbooks for birthdays as a child. She further pursued her passion for food at the Art Institute of Atlanta and obtained a degree in Culinary Arts. Carmi landed a job on the show Good Eats, which aired on the Food Network. For seven years she did everything from food research, recipe development and testing, product testing to feeding a hungry film crew. Now living in the central coast of California, Carmi enjoys the bounty of agriculture, vineyards and farmers markets at her culinary disposal. She has been using the Ankarsrum mixer for over 15 years and feels that it is hands-down the best on the market for home cooks.