Cook broccoli according to directions, or if using fresh broccoli, chop it and cook it. Drain well. Add minced garlic to the broccoli. Place broccoli in a lightly greased 1 quart casserole; set aside.
Melt 2 tbsp butter in a heavy saucepan over low heat; add flour, stirring until smooth. Cook 1 minute, stirring constantly. Gradually add milk; cook over medium heat, stirring constantly, until mixture is thickened and bubbly. Add salt and pepper; stir well. Add cream cheese, stirring until smooth.
Pour cream cheese sauce over broccoli in casserole; stir gently to combine. Sprinkle with Cheddar cheese. Melt remaining 2 tablespoons butter in a small saucepan over low heat; remove from heat and stir in breadcrumbs or ritz crackers. Sprinkle breadcrumb or ritz cracker mixture evenly over casserole.
Bake at 350 degrees for 40 minutes or until thoroughly heated.