Heat the bacon grease in a large skillet until hot.
Then add in the garlic and sauté for 1-2 minutes.
Add the onion and bell pepper in with the garlic and sauté for another 2-3 minutes.
Add the ground beef into the skillet, stirring the garlic, onions, and bell pepper into the meat. Cook on medium heat for 15 to 20 minutes, or until the meat is well cooked.
Be sure to drain off any excess oil when the meat has finished cooking.
Mix the lemon juice, chili powder, salt, black pepper, and chopped tomato into the meat, stirring until combined.
Let the taco sloppy joe mixture simmer for at least 10 minutes.
Meanwhile, prep the taco ingredients, including lettuce, tomatoes, cheddar cheese, avocados, green onions, and whatever else you like on your tacos.
Serve on toasted buns or on a bed of lettuce or spinach.