1. Preheat the oven to 425°F (220°C). Line a muffin tin with 6 tulip paper liners* and set aside. Melt the butter and let cool down a bit.

2. Mix the spelt flour, baking powder, baking soda, salt, poppy seeds, and lemon zest in a large bowl until well combined. In a second bowl mix the xylitol (or sugar) with the melted butter, oil, sour cream, egg, milk, and vanilla extract. Add the wet ingredients to the bowl with the dry ingredients and mix until just combined – do not overmix. Add the blueberries and fold them in. Divide the batter between the paper liners. Press some additional blueberries into the batter (optional) and sprinkle with some coarse sugar. Bake the muffins for 5 minutes, then reduce the temperature of the oven to 350°F (180°C) and continue baking for 20-23 minutes or until a toothpick inserted into the center of the muffins comes out clean. Take out of the oven and let cool down completely on a wire rack.