• Preheat the oven to 400 °F. Brush 9 jumbo muffin cups or 18 regular size muffin cups with melted butter.

Make the Sunflower Seed Crumble

• Combine 4 oz brown sugar, 1 ¼ all-purpose flour, 1 teaspoon cinnamon and ¼ teaspoon cardamom in a small bowl. Whisk the dry ingredients together. Toss 1 ½ oz unsalted butter cubes with the dry ingredients then use your fingers to work the butter until the bits are smaller than a pea. Toss in 2 ½ oz sunflower seeds. Use your hands to squeeze the crumble into large hunks. Set aside the crumble while making the batter.

Muffin Batter

• In a food processor or blender, grind the sunflower seeds to a fine powder. Whisk the ground seeds together with 7 ½ oz all purpose flour, 2 oz brown sugar, ½ teaspoon baking soda, 2 teaspoons baking powder, ½ teaspoon table salt, 1 teaspoon cinnamon and ¼ teaspoon cardamom in a mixing bowl. Whisk together 1 egg, 12 oz buttermilk and 2 oz vegetable oil. Pour the wet ingredients into the dry and stir just until combined. Fold in 2 cups Blueberries.
• Portion the batter between the muffin cups. The cups should be about ½ full.
• To sprinkle the crumble, grab large chunks and breaks them into smaller chunks on top of the muffins. Divide the crumb topping evenly among the muffins.
• Bake until the top of a muffin springs back when pressed, about 20 minutes. Let the muffins cool in the pan at least 10 minutes before turning out. (See note)