Preheat your oven to 350 degrees.

Combine the beef stock with 32 ounces of water and cook the shells in it according to package directions. Reserve ½ cup of the reserved pasta water.

In an oven proof skillet (see note for alternative), melt the butter, cook the garlic clove for thirty seconds, then add the bell pepper and onion and cook until tender, about 5 minutes.

Add in the ground beef, season with salt and pepper, and cook through. Drain the grease, then return to heat and stir in the cream cheese until melted.

Stir in the reserved cooking liquid from the noodles, the noodles, and the shredded mozzarella.

Top with sliced provolone. Bake for 20 to 25 minutes or until the provolone is completely melted.