Melt the butter in an oven-safe skillet or dutch oven. Stir in the orzo and the garlic with the basil and a big pinch of salt and pepper. Cook the orzo for a few minutes, stirring often, to toast it.
Pour in 1 ½ cups of the stock and the marinara sauce. Stir well. Place the skillet in the oven, uncovered, and cook for 12 to 15 minutes, until the liquid is mostly absorbed.
Remove the skillet and stir the orzo. Add the remaining ½ cup of stock. Stir in 1 cup of the grated cheese. Sprinkle the remaining grated cheese on top. Stick the skillet back in the oven and bake for 10 more minutes.
Remove the skillet and top with parmesan, fresh basil and crushed red pepper before serving.