Chewy chocolate oat squares are a cross between a cake and a flapjack and so easy to make. The kids will love making these with you. Ready in under 1hr, this simple tray bake is made with cocoa powder to give it a rich, chocolatey flavour, drizzled with melted white chocolate and packed with rolled oats. These squares are a cross between a cake and a flapjack. Store in an airtight container for up to 2 days.