Heat 1 tbsp olive oil in a skillet over medium heat. Drop a piece of garlic in and if it sizzles, add the rest of the garlic (1 tbsp garlic) and 2 oz chopped onions. Sauté for 1 minute.
Add 18 oz ground beef to the skillet. Add the seasonings on top: 1/4 tsp cumin, 1/4 tsp chili powder, 1/2 tsp paprika, 1/2 tsp salt, 1/2 tsp black pepper, 1 tsp thyme, and 1 1/2 tsp Dijon.
Allow the bottom side to sear for about 2 minutes, then break up the meat and stir to cook for another 3 minutes. Remove the skillet from heat and set aside.
Flip a muffin tray upside down and place 4 tortillas into its crannies to form a taco-shell shape. Slide into the oven to cook for 3 minutes, and repeat with the remaining 4 tortillas.
While the shells are baking, place into a bowl 1 oz red onions, 4 oz cubed tomatoes, 4 oz cubed cucumbers, and drizzle over 2 tsp lime juice. Give everything a quick toss and set aside.
As the shells finish baking, serve them with cooked beef, salsa, radish, and cheese, all kept in separate bowls. Enjoy.