Sour cream a sauce

For the recipe it is required to you:
- Vegetable broth - 2 glasses
- Sour cream - 0.5 - 0.75 glasses
- An onions{A bow} napiform - 1 piece.
- A flour{torment} - 1 st.l.
- A butter - 2 st.l.

Prepares the same as also a dairy sauce. To boil about 10 minutes. At the end of preparation for hot sauce to add sour cream which to not heat up. An onions to enter in finely cut kind, fried on oil in the beginning of preparation.