In a large bowl, combine the flour, pistachios, sugar, baking powder, soda and salt. Whisk together until combined. In a smaller bowl, whisk together the eggs, milk, vanilla extract and butter. Add the wet ingredients to the dry, mixing until smooth and combined.
Heat a large skillet or electric griddle over medium heat. Add a bit of butter if desired, then pour 1/4 cup of batter on the hot skillet and repeat, leaving an inch between pancakes. Cook until the pancakes bubble on the top and edges, about 2 minutes. Flip and cook for another minute or two until golden and set. Top the pancakes with the pistachio butter and syrup.
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.
vanilla brown butter syrup
Heat the butter over medium heat in a saucepan, whisking constantly. Cook until it bubbles and the brown bits appear on the bottom (about 4 to 5 minutes) then quickly stir in the vanilla bean paste and remove it from the heat. While warm, stir it into the maple syrup and serve immediately.