In a large saucepan, melt the butter over medium heat. Add the flour and whisk until golden, about 1 minute. Whisk in the milk and continue to cook until slightly thickened about 5-6 minutes. In 1/4 cup increments, add the cheddar cheese to the milk. Make sure each batch is completely melted before adding the next. Keep warm on the stove while you prepare your french bread pizza.

Preheat your oven to 400 degrees F and line a large baking sheet with foil. Set aside.

Make sure your steak has been in the freezer for at least 30 minutes. After 30 minutes, remove the steak from the freezer and slice thinly and against the grain. Set aside.

Heat a large nonstick skillet over medium heat. Melt the butter and add the onion. Season with salt and black pepper. Cook until tender and slightly caramelized, about 7-8 minutes. Remove the onions with a slotted spoon and transfer to a plate. Keep the skillet on over medium heat.

Add the oil to the pan, and then add the beef. Season with salt and black pepper and cook until no pink remains, about 4 minutes. Add the onions back to the pan and stir to combine. Remove from heat.

Place the two halves of the bread on the prepared baking sheet. If desired, tear out some of the bread from the center and discard or use it to make bread crumbs. Spray the two halves with nonstick spray and line each loaf with provolone cheese (about 4 slices per half). Divide the steak mixture between both halves and sprinkle with mozzarella cheese.

Place the pan in the oven and bake for 10 minutes or until the cheese is melted and the edges are slightly golden. Remove from heat.

Cut the french bread pizza into 4 sections each and drizzle with cheese sauce. Garnish with fresh oregano and enjoy immediately!