How to make
Press the garlic. Heat 2 tablespoons of butter and put the garlic in briefly, then add the flour. Stir and fry the flour.
Leave the roux aside to cool. While stirring with a wire whisk, dilute with 1 cup of hot fish broth, obtained from boiling fish fins, heads, bones, etc.
Once you mix well, add 1 more cup of broth and put it to boil on the stove for 20 minutes. Stir and finally season with salt and black pepper to taste.