Pre-heat oven to 200°C. Line a 15x20cm baking tray with parchment paper.
Add rice syrup and margarine into pan and heat until melted.
Mix dry ingredients in a large bowl. Add melted mixture to dry ingredients and mix until completely combined.
Distribute mixture evenly in tray. Pat down flat with wet hands. Bake for 25-35 mins, turning after 15 minutes. They are down when just golden at the edges, and slightly firm in the middle.
Score the tops while still warm, then turn out onto cooling racks.
Leave to cool, then cut up and enjoy!