Wash and dry produce.

Thinly slice tomato into rounds. Halve buns.

In a medium bowl, combine beef* and Fajita Spice Blend.

Form beef mixture into two equal-size balls (four balls for 4 servings); season all over with salt and pepper.

Heat a drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Add beef and flatten each ball with a spatula to create very thin patties. (TIP: Do so carefully; oil may splatter a bit.) Cook to desired doneness, 3-4 minutes per side. (Don’t worry if the patties aren’t perfectly round—those irregular edges will turn crispy.)

In the last 1-2 minutes of cooking, top patties with Mexican cheese blend and cover pan to melt cheese.

While patties cook, toast buns until golden brown.

Spread top buns with guacamole and hot sauce to taste. Place patties, tomato, and a few tortilla chips on bottom buns. Close buns.

Divide burgers between plates. Serve with remaining tortilla chips on the side.