portabella burger

my new nutribullet comes with a recipe book and there are some really great ones i'm starting to try. i've always wanted to make a portabella burger (mushrooms are my weakness) and i finally got a great recipe!

makes 4 burgers/serves 4 people
ingredients:

• 4 portabella mushrooms, stems removed
• 1 medium onion, cut into 1/2 inch slices
•  2 tbsp olive oil
• 3/4 tsp salt, divided
• 1/2 tsp ground black pepper, divided
• 1 avocado, sliced
• 1/2 tsp minced garlic
• 4 whole wheat buns or whole wheat english muffins, lightly toasted (i used ciabatta bread)
• 4 jarred roasted red peppers
• handful of spinach- optional

how to:

1. brush mushrooms and onion slices with oil; sprinkle with 1/2 tsp of salt and 1/4 tsp of pepper
2. heat large skillet or grill pan over medium heat until hot. add mushrooms; cook until tender, 8 to 10 minutes, turning once. transfer mushrooms to plate, cavity side up; cover to keep warm
3. in same skillet, cook onion slices until golden, about 8 minutes, turning occasionally
4. meanwhile, combine 1/2 avocado, garlic, and remaining 1/4 tsp each salt and pepper; mash until smooth, you can also skip this step and use any pre-made guacamole 
5. spoon onions and roasted peppers into mushrooms cavities, divided equally. spread smooth avocado mixture/guacamole on the bottom of each bun; top each with stuffed mushrooms
6. top with remaining sliced avocado (i also added spinach and tomato slice, although tomato is really not needed, so next time i won't). cover with tops of buns