It's really up to you how much of this crunchy oat topping you want to sprinkle on your fruit or yoghurt. A little does go a long way.
Preheat the oven to 180C/160C Fan/Gas 4.
Put the oats and seeds into a bowl. Melt the butter, brown sugar and cinnamon gently in a pan. When melted, pour into the oats and seeds and stir until completely coated.
Pour the mixture onto a baking tray lined with foil or baking paper, spread it out into an even layer. Bake in the oven for 10 minutes, stirring twice, until it is golden brown. Allow to cool completely, then store in an airtight container. It will keep for about a week.