Preheat the oven to 425°F. Line a large rimmed baking tray with parchment paper. Set aside.
In a large skillet, brown the ground beef over medium-high heat for 4 to 5 minutes or until no pink remains.
Using a slotted spoon, remove the browned ground beef and place it on a plate. Drain the excess fat from the skillet.
To the skillet, add the butter and finely chopped onions. Saute on medium heat for 2 to 3 minutes or until the onions are soft and translucent.
Stir in the tomato sauce, ketchup, Worcestershire sauce, white vinegar, yellow mustard, brown sugar, garlic powder, onion powder, salt, black pepper, and reserved cooked ground beef to the skillet of sauteed onions.
Bring the sauce mixture to a boil, reduce heat and simmer for 7 to 8 minutes or until the sloppy Joe mixture has thickened. While your sauce simmers, you can prepare your Five Cheese Texas Toast.
Place the 8 slices of frozen Five Cheese Texas Toast onto the prepared baking tray. Be sure that the shredded cheese side is facing up. Bake for 6 minutes.
Remove the baking sheet from the oven and top each of the slices of texas toast with the sloppy Joe mixture (a little less than a ½ cup each).
Top each slice of sloppy Joe Texas toast with ¼ cup of the shredded mozzarella cheese. Be sure to mound it in the center of the sloppy Joe mixture. As it melts, it will spread to cover the entire top of the texas toast without running down the sides too much.
Place the baking sheet of sloppy Joe Texas toast back into the oven for an additional 3 to 4 minutes to finish baking the toast and to melt the cheese.
We recommend shredding your cheese from the block for this recipe. Pre-shredded cheese tends to have a preservative coating that prevents the cheese from melting well.
Oven temperatures vary and may need to be recalibrated periodically to ensure they are accurate. Make sure to keep a close eye on your toast as the suggested baking time approaches.
Don’t wait to serve these. Sloppy Joes are best served as soon as they’re made. Adding filling to the bread and letting it sit for more than a few minutes can make your bread soggy. Instead, if you need to make this recipe ahead of time, keep your filling and bread separate until you’re ready to serve.