Gather your ingredients. In a heavy-duty skillet, cook bacon over medium-high heat until crisp. Remove the bacon with a slotted spoon and drain on a paper towel. Save about 2 tablespoons of the bacon drippings.

Cook the chopped onions in the bacon grease over medium heat until tender and translucent. With a wooden spoon, stir in the all-purpose flour, kosher salt and black pepper and cook over low heat until the roux turns golden brown.

Pour in the chopped tomatoes and tomato juice and bring to a boil. Reduce to low heat and simmer until it thickens, about 15 minutes. Stir in the reserved bacon pieces. Make sure to taste your gravy before serving. Depending on the acidity of the diced tomatoes, the gravy might need a pinch of sugar.