Add 1-2 tablespoons oil to skillet over medium-low heat. Add tortillas, one at a time. Cook for about 2-3 minutes per side, until just brown and crisp. Remove tortilla to a wire cooling rack with small bowls inverted over a baking sheet to cool. Place the tortilla onto the inverted bowls and using the tongs, pull the edges over to form a loose bowl shape with the cooked tortilla. Repeat until all tortillas have been prepared.
Wipe skillet clean with paper towels and add ground beef and taco seasoning to the skillet over medium-low heat. Brown ground beef, drain any excess grease, and set aside.
Meanwhile, in a small saucepan prepare the dressing by adding the enchilada sauce, Coke, brown sugar and Sriracha sauce. Cook until reduced and thickened enough to coat the back of a spoon. Set aside.
To assemble taco salads, place a prepared tortilla shell on each plate. Add about 1/4 cup refried beans, top with about 1/2 cup to 1 cup of prepared beef, then add lettuce greens, onion slices, tomatoes, and a dollop of sour cream.
Drizzle with a tablespoon or two of prepared sauce that has been set aside from earlier. Serve immediately.