A hot emulsified sauce, very easy to make and absolutely delicious; you will be amazed by the dark purple color.

In a blender, puree the blackberry with the lemon juice, sugar, wine, garlic, salt and pepper. Strain the puree in a small saucepan.

Bring to a boil and reduce the puree to ¼ cup. On low heat, quickly whisk in the butter into the reduced puree, a few cubes of butter at a time. Do not let the sauce boil again.

Taste and rectify the seasoning and serve immediately with grilled fish.