Cook the pasta, drain and set aside.

While the pasta is cooking preheat your oven to 350° F and prepare the sauce. Melt butter over moderate heat in a heavy saucepan. Add flour and whisk for about 3 minutes to make a roux but dont let it brown. Add the hot milk in a steady stream, whisking until it thickens but dont let it boil. Reduce heat to low, add two-thirds of the cheddar to the sauce and stir until melted. Add salt and pepper. Remove from heat and stir in the pasta and cherry tomatoes.

Grease a shallow 3-quart baking dish and transfer the pasta into it. Top with the remaining cheddar. Bake for 30-35 minutes until the top is golden brown.