Thaw and drain raspberries, reserving 1 tablespoon juice. Mash raspberries. Press through a fine-mesh strainer into a small saucepan; discard seeds.
Add apple butter and red-hots to strained raspberries; cook over medium heat until candies are dissolved, stirring occasionally. Combine cornstarch and reserved juice until smooth; stir into berry mixture. Bring to a boil; cook and stir over medium heat for 1-2 minutes or until thickened.
To serve warm, transfer to a small fondue pot and keep warm. Or, to serve cold, refrigerate until chilled. Serve with fruit.