Easy Pasta Alfredo

Ingredients

• 14 cup butter
• 4 teaspoons minced garlic
• 1 pint half-and-half cream
• 12 pint heavy cream
• 8 ounces shredded extra-sharp cheddar cheese
• 1 cup canned grated parmesan cheese
• 1 dash nutmeg
• 1 dash parsley flakes
• salt and pepper
• 1 (4 ounce) can mushrooms, drained (optional)
• 1 lb cooked chicken breasts (optional) or 1 lb cooked shrimp (optional) or 1 lb cooked crabmeat (optional)
• 1 lb pasta, prepared according package directions