Slice croissants in half horizontally. In 15 x 10 x 2-1/2-inch oval baking dish, arrange bottoms of sliced croissants, cut sides up. Scatter raisins over top. Cover with croissant tops, cut sides down. Make sure raisins are completely covered by croissants or they will burn while baking. Pour egg mixture over croissants. Let stand 10 minutes, pressing croissants down gently.