Preheat a large skillet or griddle over medium-high heat and lightly grease it with oil or nonstick spray.
Divide the ground beef into 8 equal balls.
Place a tortilla on a flat surface, set a beef ball in the center, and flatten it thinly onto the tortilla using your hands or the bottom of a plate.
Season each smashed patty side with salt, pepper, and garlic powder.
Transfer each tortilla, beef side down, onto the hot skillet. Press down gently with a spatula and cook for 2-3 minutes until the beef is browned and crispy.
Flip carefully and cook another 1-2 minutes to warm and lightly toast the tortilla.
Remove from heat and top immediately with cheese, if using, so it melts slightly.
Assemble with your favorite toppings and serve warm.