Line a 20cm square baking tin with baking parchment. Melt the nut butter (we used a mix of peanut and almond) in a pan over a low heat with the maple syrup, plant-based milk and vanilla extract until smooth. Take off the heat and mix in the porridge oats, ground flaxseeds and 1/2 tsp fine sea salt and cinnamon. Stir in the chocolate chips (ensure they’re vegan if needed) or dried fruit and nuts. Spoon into the tin and level out the top. Leave for 15 mins, then transfer to the fridge to set for at least 2 hrs. Cut into 16 squares. Will keep chilled in an airtight container for up to five days.