Heat oil in a large pot on medium-high heat. Sauté onions and garlic till the onions are translucent and garlic is fragrant.
Add in the ground beef and mix it using a spatula till the beef is evenly browned.
Once the beef is browned, add kidney beans, white vinegar, and crushed tomato sauce to the pot.
Add all of the spices and seasonings - the chili powder, cumin, paprika, brown sugar, black pepper, and salt - to the pan and stir to combine everything with the beef.
Once combined, reduce the stove to medium-low heat. Cover the pot with a lid and allow the Texas chili to simmer for 30-40 minutes.
Stir the chili occasionally to prevent it from burning.
Close with a lid and let it simmer for 30 to 40 minutes.
OPTIONAL STEP: Around 30 to 40 minutes, if the chili looks too watery, then add the flour. Mix and let it cook for another 10 to 15 minutes or until you feel the chili has reached the right thickness.
Once the chili has become slightly thick, you can remove it from the heat. Let it sit for 5 minutes.
Serve it warm in a bowl. Top it off with some shredded cheddar cheese, sliced jalapenos, sour cream, crushed crackers, or any of your favorite toppings!