The I'm Possible Burger is a great imitation of the Impossible Burger and the Beyond Burger, and it's both simple and inexpensive to make at home with common items from your local grocery.
Cook the rice and set aside one cup.
Sauté the mushrooms until tender and browned.
Coarsely chop the tempeh into 1/2 inch cups.
Add all ingredients to a large bowl food processor and process until mostly chopped, and incorporated, and the mix resembles "hamburger."
Divide into eight pieces (or more or less, depending on how large you want your burgers), and shape into patties.
Sauté patties in a pan with optional oil and serve on buns with your choice of condiments.