1. Preheat the oven to 350°F (175°C). Line a baking sheet with baking parchment and set aside. The cookies are better when you use roasted hazelnuts. In case you want to roast the hazelnuts, place them on the baking sheet and let roast in the oven for about 8-10 minutes. Take them out, place them in a damp kitchen towel, and let cool down for a moment, then remove the skins. Chop finely and set aside.

2. Add the butter and sugars to a large bowl and mix on high speed until light and fluffy. Add the egg and vanilla extract and mix until well combined. Add the rolled oats and mix until just combined. Mix the spelt flour with baking powder, baking soda, and salt and add to the bowl – mix until just combined. Add the chopped chocolate and chopped hazelnuts and fold in. Use a cookie scoop or tablespoons to place dough portions on the prepared baking sheet with enough space in between. Flatten slightly and bake for about 10 minutes – the edges should have gotten a tiny bit of color, but the centers of the cookies should still be soft. Take out of the oven and let cool down on the baking sheet for some time, transfer to a wire rack and let cool down completely. Repeat with the remaining dough.