• Preheat the oven to 180°C (350°F). Line a 12-cup muffin pan with paper liners.

Make the cupcakes:

• Optional: Add the sugar and lemon zest to a large mixing bowl. Use your fingertips to rub them together until fragrant.
• Add all the dry ingredients to a large mixing bowl and whisk until there are no lumps. Add all the wet ingredients and mix until just combined.
• Use an ice cream scoop or a large spoon to divide the batter between your cupcake liners. Each cupcake cavity should be three-quarters full.
• Bake the cupcakes for 20-25 minutes. They are ready when you insert a toothpick in the center of a cupcake and it comes out with no wet batter on it (a few crumbs are fine).
• Cool the cupcakes in the tray for 5 minutes then transfer them to a cooling rack.

Make the frosting:

• Add the butter to a large bowl (if using a hand mixer) or bowl of a stand mixer with the whisk attachment. Beat until light and fluffy. Add the powdered sugar, lemon juice and vanilla and beat until just combined. Taste the frosting and adjust if needed. If the frosting is too thin, add more sugar and beat or add more lemon juice or non-dairy milk if it's too thick.
• When the cupcakes have fully cooled, use a spatula or piping bag to frost the cupcakes. Decorate as desired.
• Serve the cupcakes immediately. Store the unfrosted cupcakes in an airtight container at room temperature for up to 3 days. If your cupcakes are frosting, keep them at room temperature for 1 day or in the fridge for up to 3 days. Allow the cupcakes to come to room temperature before serving. The cupcakes freeze well but I recommend storing them separately from the frosting.