Making Ground Beef Tostadas is straightforward when you follow these steps:

1. Heat the Oil: In a large skillet, heat olive oil over medium heat.
2. Cook the Onion: Add the chopped onion and sauté until translucent, about 3-5 minutes.
3. Add Garlic: Stir in the minced garlic and continue to cook for an additional minute.
4. Brown the Beef: Add the ground beef to the skillet and cook until browned, breaking it apart with a spatula.
5. Season the Mixture: Sprinkle in chili powder, cumin, paprika, salt, and pepper. Stir to combine and cook for another 3-5 minutes until the spices are fragrant.
6. Prepare Tostada Shells: While the beef is cooking, preheat the oven to 375°F (190°C). Place tostada shells on a baking sheet and heat them in the oven for about 5-7 minutes or until crispy.
7. Assemble Tostadas: Once the shells are ready, remove them from the oven. Top each tostada with a generous spoonful of seasoned beef.
8. Add Toppings: Layer on the shredded lettuce, diced tomatoes, and shredded cheese.
9. Finish with Garnishes: Add a dollop of sour cream and guacamole. Sprinkle with fresh cilantro for a burst of flavor.
10. Serve and Enjoy: Arrange the tostadas on a serving platter and get ready to dig in!