Preheat the oven to 150˚C/gas mark 2. Grease an 18cm x 25cm baking tin and line the base with non-stick baking paper.
Mix the oats, seeds and almonds in a roasting tin, then toast in the oven for 10 minutes. Remove from the oven and leave to cool for 10 minutes.
Meanwhile, melt the butter, sugar and honey in a large saucepan, stirring until combined. Remove from the heat and add the oat mixture and dried cranberries. Mix until well coated.
Tip the mixture into the prepared tin, pressing down lightly to level it. Bake in the oven for 25 to 30 minutes, then remove from the oven and leave to cool until set. Cut into 12 bars and store in an airtight container.