1/4 c. butter
1/2 c. chopped onion
1/2 c. chopped carrot
1/2 c. chopped celery
1/4 c. flour
1 1/2 tbsp. cornstarch
1 qt. chicken stock
1 qt. milk
1/8 tsp. baking soda
1 to 1 1/2 c. grated cheddar cheese
1 tbsp. parsley

Melt butter in large pot. Add onions, carrots, and celery. Saute over low heat until soft. Add flour and cornstarch. Cook until bubbly. Add stock and milk. Cook gently until sauce is smooth. Add baking soda and cheese. Season with salt and pepper. Add parsley before serving.