Dill Sauce - cooking recipe

Ingredients

2 Tbsp. butter
2 Tbsp. flour
2 c. stock
2 Tbsp. dill, chopped
1 1/2 Tbsp. vinegar
1/2 to 1 Tbsp. sugar
1 egg yolk
salt

Preparation

Melt butter; add flour until well blended.
Add stock, gradually, while stirring, then cook slowly for 10 minutes, stirring occasionally.
Add dill, vinegar and sugar.
Season to taste.
Remove from heat and add egg yolk.