• Preheat the oven to 375°F (190°C). Line a 12-hole muffin pan with muffin liners. Or use two muffin pans if the muffin liners are on the smaller side. This recipe will make 16 regular muffins or 12 larger muffins.
• In a large bowl, whisk together the flour and brown sugar, until well combined and no lumps. Add the blueberries; stir to combine.
• In a medium bowl, whisk together the butter, buttermilk, eggs and zest until well combined. Add the butter mixture to the flour mixture; stir until combined. Spoon the mixture into the muffin liners – this is easiest if you use a spring-loaded ice cream scoop; sprinkle each muffin with turbinado sugar. Bake for 20 to 22 minutes until lightly golden and a skewer comes out clean when inserted into the center of a muffin. Let stand in the pan for 5 minutes before removing to a wire rack set over a baking sheet.

To make the glaze:

• While the muffins are cooking, whisk the powdered sugar and lime juice together until smooth, adding enough lime juice to create a thick, runny paste. Drizzle the glaze over the warm, not hot, muffins. Let sit until the glaze is set. Makes 12 large muffins or 16 smaller muffins.