Preheat the oven to 350 deg and set rack in the middle of the oven. Prepare cupcake pan with paper cupcake liners and set aside

Sift together the flour and baking powder. Set aside

Using a stand mixer cream egg and sugar until pale and slightly thickened, about 2 -3 minutes. Add in the melted butter, lemon juice, zest, ricotta, butermilk and extracts until well mixed on medium speed. Lower the speed and slowly add in the flour mixture until just incorporated. Stop the mixer and scrape down the sides with a spatula. Mix again on medium for 30 seconds.

Spoon the batter into the cups of the prepared pans about ¾ of the way full. Bake for 18-20 min until golden or the tops bounce back when slightly pressed or a skewer comes out clean. Cool in pans for 5 min then remove the cupcakes and cool completely on wire racks before frosting.

If filling cut out a hole in the middle of the cupcake about ¾” down ( an apple corer works great for this) and fill with a heaping tbsp. of curd. You can fill to the top or replace a tiny bit of the piece of cupcake that was removed.

Combine sugar and zest in a small bowl and rub together with fingers until thoroughly mixed and fragrant.

Set up a double boiler or a pan of water and a stainless steel bowl that fits on the pan but not touching the water. Bring the water to a boil and then let simmer. In the bowl whisk together the egg yolks, whole egg, sugar and zest mixture and juices. Set the pan in the double boiler or over the pan of simmering water and whisk until thickened, about the consistency of a thick pudding or custard.

Remove from the heat and whisk in one table spoon of butter at a time and whisk until it is fully combined before adding in the next tablespoon. Once all the butter is combined pour the mixture into a clean bowl (glass or stainless doesn’t matter) and press a layer of plastic wrap over the top of the curd so it doesn’t form a skin. Cover the bowl and refrigerate at least 2 hours until chilled before using. This can be made up to two weeks ahead of time.

Separate the egg whites into the bowl of a standing mixer fitted with the wire whip/whisk attachment.

Measure 11/4 cup sugar, salt and the water into a 1-quart, heavy- bottomed saucepan. Gently stir to combine.

Measure the remaining ¼ cup sugar into a small bowl and set aside.

Cut the butter into tablespoon-sized pieces and set aside in a medium bowl.

To make the sugar syrup, place the candy thermometer in the saucepan and heat the mixture over medium-high heat. Partially cover with a lid to capture the evaporating water—this helps to moisten the sides of the saucepan to prevent sugar crystals from forming.

With the mixer on high speed, begin whipping the egg whites to stiff peaks. When the peaks are stiff, you have a meringue, lower the mixer to medium speed.

Keep the mixer running and pour the ¼ cup of sugar into the meringue, and keep whipping

Raise the heat under the sugar syrup to bring the syrup to 245°F, if it is not there already. When the syrup is at 245°F, immediately remove from heat, remove the thermometer and slowly pour the syrup into the meringue, while the whisk is still mixing.

After 1 to 2 minutes reduce the mixer speed to medium-high for 3 to 4 minutes, or until the meringue is cooled. The bowl should feel cool to touch. This takes about 7 minutes. Add the butter 1 tablespoon at a time. Increase the mixer speed to high for 1 to 2 minutes, or until the butter is fully incorporated. If it looks soupy, keep mixing on high until it comes together. You will hear and see the difference once it thickens up to proper consistency