Preheat broiler. Slice baguette into 16 diagonal slices. Place bread on broiler pan and broil 4 minutes or until golden brown, turning once; set aside.
Bring balsamic vinegar and sugar to a boil in a saucepan over medium heat. Boil 10 minutes or until reduced to ½ cup. Remove from heat and stir in blackberries. Cool completely.
Combine chevre, garlic, Italian seasoning, pepper and milk in a blender or food processor and blend until smooth. Cut prosciutto slices crosswise into 3 pieces.
To assemble, brush balsamic reduction on each slice of baguette and spread with about 1 1/2 teaspoons cheese mixture.
Top with 1 piece prosciutto and 1 blackberry from the balsamic reduction. Repeat with remaining ingredients.
