Grease a 20cm square baking tin or dish and line with baking paper.
Place butter, Chelsea Caster Sugar and honey in a large saucepan. Cook over medium heat until butter has melted. Increase heat a little and bring to the boil; boil for 3 minutes.
Remove from heat, add rice bubbles and stir well. Transfer to prepared dish and use a spatula to flatten out. Top with sprinkles, if desired. Slice while still slightly warm.