Make the sauce: In a small bowl, stir together all sauce ingredients until well combined. Set aside.
Form the beef balls: Divide the ground beef into 6 equal portions and roll into loose balls. Season with salt, pepper, and garlic powder.
Preheat skillet: Heat a griddle or cast-iron skillet over medium-high heat. Lightly oil the surface.
Smash and sear: Place one beef ball on the skillet, top with a tortilla, and press down firmly with a spatula to flatten the beef into the tortilla. Cook for 2–3 minutes, until the beef is crispy and browned. Flip carefully.
Melt cheese: Immediately add a slice of cheese to the cooked side of the beef. Cook another 1–2 minutes, until cheese melts and tortilla is golden. Remove and repeat for remaining tacos.
Assemble and serve: Top with burger sauce and your favorite toppings. Fold and serve hot like a taco.