Sort through the blackberries, discarding any that don’t look good. Cut any large ones in half, set the berries aside.

In a separate bowl, whisk together milk, yogurt, vegetable oil, eggs, lemon zest and vanilla extract.

Add wet ingredients mixture all at once to the bowl of dry ingredients, stir just until combined, then fold in the blackberries.

Divide batter between 12 prepared muffin cups, filling each to almost full. Sprinkle with coarse sugar, if using.

Bake in a 375 degree F oven for 25 to 28 minutes or until golden and a wooden toothpick inserted in centers comes out clean.

Cool in muffin cups on a wire rack for 5 minutes.

Remove from muffin cups; serve warm.

Uneaten muffins can be left on the cooling rack until they’re cooled to room temperature, then transferred to an airtight container in the fridge for up to 5 days or so.

Best served reheated, but they’re also great straight from the fridge!