Preheat the Oven. Preheat your oven to 180ºC (350ºF) (fan setting). This ensures it’s at the right temperature for baking your oat bars. Line a 9-inch baking tin with parchment paper, allowing some overhang for easy removal later.
Combine Dry Ingredients. In a mixing bowl, stir together: 180g oats, 1 grated apple, 8 chopped dates, 2 tablespoons chia seeds. Mix these dry ingredients well to ensure everything is evenly distributed.
Prepare the Wet Mixture. In another bowl, whisk together: 100ml milk, 2 eggs, 30g honey, 1 teaspoon vanilla extract. Whisk until combined, and the mixture is smooth.
Combine Wet and Dry Ingredients. Pour the wet mixture into the bowl with the dry ingredients. Stir everything together until well combined. The mixture should be thick and sticky.
Transfer to Baking Tin. Transfer the mixture into your prepared baking tin. Use a fork or spatula to smooth the top, making sure it’s even.
Bake.Place the baking tin in the preheated oven and bake for 20-25 minutes. The oat bars should be golden brown around the edges and set in the middle.
Cool and Slice. Once baked, remove the tin from the oven and let it cool in the tin for about 10 minutes. Then, lift the bars out using the parchment overhang and place them on a wire rack to cool completely. Once cooled, slice into bars or squares.