My go to mushroom sauce for whenever! It's great with just about anything, crepes, potoato bourekas, chicken wellingtons or in a pastry shell. Whoever I have passed it on to thanks me. It freezes really well, but leave the last step (with the starch for right before you serve.)
2 large onions diced
2 sticks celery diced
½ green pepper diced
1 lb mushroom sliced-canned is ok
0 pinch salt, pepper, paprika to taste
½ tsp sugar
4 Tbsp margarine(½ stick)
½ cup water
1½ Tbsp chicken soup mix
Put all ingredients in a pot and bring to a boil. Simmer on flame for 45 minutes to an hour.
When ready to serve, take boiling hot water and mix with 2 tbsp corn starch, mix well. Add this mixture to the pot and cook for another 2 minutes.