Place the lemon quarters in the food processor, making sure to remove any seeds. Using the blade attachment, blitz until pureed. It is nice to see small pieces of lemon peel in the final baking mix.
Add all the other ingredients. Pulse until smooth.
Place a spoon of the batter into each mini cupcake case.
Bake at 350F for 10-12 minutes. Test the center with your finger. When springs back, it’s done.
Frosting
Mix the softened cream cheese with the yogurt with a fork until smooth.
Add the lemon zest and juice.
Slowly add stevia until it is to your taste. Some will prefer it with no sweetener and quite a sour taste, others are not ready for this and may require more sweetener.
When the cupcakes are completely cool, decorate with the frosting. Top each one with a blueberry or a tiny piece of lemon.