1Line 2 (8x4-inch) loaf pans with plastic wrap, allowing 4 inches wrap to hang over short ends of pans. In food processor bowl with metal blade, place quartered strawberries. Cover; process with on-and-off pulses until almost pureed but with a few small pieces remaining. In large bowl, stir pureed strawberries, milk, liqueur and orange peel until well mixed.
2Trim or brush any dark brown crust from angel food cake; cut cake into 3/4-inch cubes. In large bowl, beat whipping cream with electric mixer on high speed until stiff peaks form. Fold whipped cream and cake cubes into strawberry mixture. Spoon mixture evenly into pans. Fold plastic wrap over mixture. Freeze at least 5 hours until firm.
3To serve, remove dessert from freezer 5 to10 minutes before serving. Unwrap and unmold onto serving platter; remove plastic wrap. Garnish tops of loaves with strawberry slices.