Preheat oven to 350 degrees.
Generously grease a 9 x 9 casserole pan with butter.
Bring large pot of water to boil.
Add trimmed, cleaned green beans to boiling water.
Cook about 1-2 minutes just to blanch them.
Drain & add to ice water bath to stop cooking. Drain well & set aside.
Meanwhile in pan on top of stove melt butter over medium heat.
Add onion & garlic & cook 2-3 minutes.
Then half & half cream, & creamed cheese and stir another couple minutes till thickened.
When thickened add 6 ounces of sharp cheddar cheese & stir till completely melted.
Salt & pepper to taste.
Put drained green beans in buttered casserole pan, top with sauce and remaining cheddar cheese.
Instructions for topping:
pulse crackers in food processor till finely chopped.
put in bowl with parmesan cheese and stir.
sprinkle on top of green beans.
optional: sprinkle casserole with paprika
Bake in preheated oven covered 30 minutes
Remove cover and cook an additional 10 minutes.
Allow 10 minutes prior to serving.