In a skillet, warm olive oil over medium heat. Once hot, add the lean ground beef and diced onions. Cook until the beef is no longer pink and the onions are soft, about 5-7 minutes.

Drain any excess fat from the skillet. Stir in the sweet relish, yellow mustard, and ketchup until well combined, creating a flavorful mixture that’s reminiscent of a classic cheeseburger.

Toss in the shredded cheddar cheese. Stir until the cheese fully melts and everything is well mixed together. Season with salt and pepper to taste.

Lay out your flour tortillas on a flat surface. Place about 1/4 cup of the beef mixture onto each tortilla, then roll them tightly, sealing in all that delicious flavor.

Brush the tops of the rolled taquitos with a drizzle of olive oil. Arrange them seam side down on a baking sheet to ensure they hold together while baking.

Preheat your oven to 350°F. Bake the taquitos for 15-20 minutes, or until they turn a golden brown and are crispy to the touch.