BRING water, piloncillo, cinnamon and cloves to boil in medium saucepan; simmer on medium heat 20 min. or until syrup-like consistency, stirring occasionally. Remove from heat; keep warm.
HEAT oven to 350ºF. Toss bread cubes with butter; spread onto baking sheet. Bake 10 min. Transfer to large bowl. Add raisins and nuts; mix lightly. Strain syrup; discard cinnamon stick and cloves. Add syrup to bread mixture; mix well. Let stand 10 min., stirring frequently. Meanwhile, combine cheeses.
SPOON half the bread mixture into 2-qt. casserole; sprinkle with half the cheese mixture. Repeat layers; cover.
BAKE 25 min. or until cheese is melted and golden brown, uncovering the last 5 min.