Hot Broccoli Cheese Dip

3/4 cup butter
3 stalks celery, thinly sliced
1 onion, chopped
1 4-oz can sliced mushrooms, drained
3 Tbs flour
1 10 3/4-oz can cream of celery soup
1 cup shredded cheddar cheese
1 10-oz package chopped broccoli

In a small skillet, melt the butter and saute the celery, onion and mushrooms. Stir in the flour. Place into a lightly greased slow cooker and stir in remaining ingredients. Cover cook on High, stirring about every 15 minutes until the cheese is melted. Turn to Low for 2 to 4 hours or until ready to serve.