Heat a skillet over medium heat. Add diced onions and cook until translucent, about 3 minutes, releasing a fragrant aroma.
Add the ground meat or plant-based mince to the skillet. Break it apart with a spatula and cook until browned and cooked through, about 8 minutes. Stir in cumin and cook for another minute to develop flavor.
While the filling simmers, warm the tortillas in a dry skillet over medium heat for about 30 seconds per side until they are soft and pliable.
Place a warm tortilla on a plate or taco holder. Spoon a generous amount of the savory filling into the center of each tortilla, spreading it slightly.
Sprinkle shredded cheese over the hot filling so it begins to melt slightly, adding a gooey texture.
Top each taco with chopped lettuce for crunch and freshness, balancing the savory filling.
Drizzle spicy salsa over the toppings to add heat and smoky flavor, enhancing the visual appeal.
Finish with a few slices of pickled jalapeños or other pickled vegetables for a bright, vinegary bite.
Finish each taco with a dollop of sour cream or crema for a cool, tangy contrast to the spicy toppings.
Serve the Halloween tacos immediately, allowing everyone to enjoy the colorful, flavorful bites while the tortillas are warm and the cheese is melty.