In a large mixing bowl, combine the ground beef, salsa, and cumin together.
Divide into equal four portions, and form into patties.
Cook burgers over medium-high heat for 4 minutes, flip and continue to cook until barely any pink remains.
Top each burger patty with cheese, cover with a lid and cook until the cheese has melted.
Mash the avocados with lime juice, salt and pepper. Set aside. (or substitute guacamole)
Serve the Tex-Mex Burgers on toasted buns with lettuce and topped with the mashed avocado and additional salsa.
Notes
To make your burgers spicier: Use Pepper Jack Cheese. Use spicy salsa. Add cayenne powder with the cumin.
The salsa will add moisture to your finished burgers, so make sure your salsa is on the "dry" side. I scooped it out with a fork and let it drip for a bit to get as little liquid as possible.
I used grated Monterrey Jack cheese because that was what I had on hand. Grated or sliced both work great.