• Preheat the oven to 400 degrees F. Place the butter in a (8 or 9 inch) cast iron (or oven safe!) skillet or baking dish. Place it in the oven just until it melts.
• Whisk together the flour, sugar, cinnamon and salt in a large bowl. In a smaller bowl, whisk together the eggs, milk and vanilla paste. Stir the wet ingredients into the dry, whisk until no lumps remain. Take the skillet out of the oven and pout the batter in. Place it right back in the oven and bake for 18 to 20 minutes, or until puffed and golden.
• Remove the dutch baby and immediately add a few scoops of the pistachio butter. Dust on the pistachio sugar and top with blueberries. Serve warm!

pistachio butter

• Whisk together the butter and pistachios until combined. You can use it just like this or place it in the fridge to harden a bit. If so, you can wrap it tightly in plastic wrap and store it until needed.

pistachio sugar

• Whisk together the pistachios and powdered sugar. Use a fine mesh strainer to sprinkle.