1. Preheat the oven to 390°F (200°C). Line two muffin tins with paper liners (20-22) and set aside. Wash and dry the blueberries. Mash the banana(s) and set aside.

2. Mix the flour with poppy seeds, baking powder, ground cardamom, cinnamon, and salt. Set side. Melt the butter and add together with the xylitol (or sugar) to a large bowl and mix until well combined. Add the eggs and vanilla extract and mix in. Next, add sour cream and mashed bananas and stir in. Add the flour mixture and fold in – you want to mix just enough, so you can’t see dry spots anymore. Add the blueberries and fold in. Divide the batter between the paper liners – you want them to be almost full. Press some additional blueberries into the batter if you like and sprinkle with some chopped walnuts and coarse brown sugar (optional).

3. Bake the first batch of muffins for 22-24 minutes or until a toothpick inserted into the center of a muffin comes out clean. Take out of the oven and let cool down a bit inside the muffin tin, then remove and let cool down completely on a wire rack. Repeat with the remaining batter/muffins.

Tip 1: If you have a convection oven, you can easily bake two muffin trays at once – if you do so, reduce the oven temperature to 350°F (180°C).

Tip 2: You can also bake larger muffins here with tulip paper molds*. You can almost double the amount of batter per muffin. The baking time will be probably 2-3 minutes longer.