Trim fat from beef and cut crosswise into 1/2" slices. In a large skillet heat 2 T. oil or wine, add onion and garlic and cook until tender.
Add beef and brown well on both sides.
Add mushrooms and saute 5 minutes longer.
Mix the flour with the beef, then add water, soup base, garlic, salt and pepper to the skillet. Bring to the boiling point, stirring constantly. Reduce heat, continue to stir and simmer until thickened.
Add sour cream and mix well. Continue to simmer until hot, but do not boil.
Although spelt is actually a type of wheat flour, most people with wheat allergies can digest spelt flour with no problem. Obviously, you should not eat spelt if it is a problem for you.