Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper or lightly oil it.

In a large skillet over medium-high heat, brown the ground beef, breaking it into small crumbles, about 5 minutes. Drain off any excess fat.

Add the taco seasoning and water to the skillet. Stir and simmer until the liquid thickens and coats the beef, about 2 minutes. Set aside.

Spread a thin, even layer of refried beans on 4 of the tortillas. Top each with the remaining 4 tortillas to create a double-layered base. This prevents sogginess.

Using a pastry brush, lightly coat the top of each stacked tortilla with olive oil. Place them on the prepared baking sheet.

Bake the tortilla stacks for 5 minutes. They should be just starting to brown and crisp on the edges.

Remove the baking sheet from the oven. Spread a generous spoonful of salsa over each tortilla stack. Top evenly with the seasoned beef.

Sprinkle the shredded cheese over the beef. Return to the oven and bake for another 8-10 minutes, until the cheese is melted and bubbly and the tortilla edges are deep golden and crisp.

Let the pizzas rest on the baking sheet for 2 minutes. Transfer to a cutting board and slice each into 4 wedges using a sharp knife or pizza cutter.

Top each pizza with a dollop of sour cream, shredded lettuce, diced tomato, black olives, cilantro, and jalapeño slices if using. Serve immediately with lime wedges.