Step 1

Preheat oven to 375 F. Line a muffin tin with cupcake liners.

Step 2

In a large bowl whisk to combine the flour, baking powder, baking soda, chia seeds, sugar, lemon zest and salt.

Step 3

To a medium sized bowl, add the melted butter, buttermilk, vanilla extract, egg, and lemon juice. Whisk to combine.

Step 4

Pour the wet ingredients into the dry ingredients and stir gently until just combined. Do not overmix. Use an ice cream scoop to evenly distribute the batter into the prepared cupcake tin. (The cupcakes will be filled to the rim with batter). Mix the extra lemon zest and turbinado sugar together in a small bowl and top the muffins with it. Bake 15-18 minutes or until a toothpick comes out without wet crumbs when inserted in the middle of a muffin.

Step 5

Let cool in tin for 5-10 minutes then transfer muffins to a wire rack to cool completely. Once cooled, drizzle with icing, if desired.

Step 6

In a medium sized bowl, stir together the powdered sugar and the lemon juice. Add up to a half tablespoon more lemon juice if icing is too thick. Spread or drizzle over the cooled muffins.