“Hmmmm,” I thought, as I mulled over the empty cookie jar, “I wonder…” and these were born.

A note on custard powder – I use Bird’s, which is the classic English brand, but I read on the interwebbies that there are a few US companies that make it too, and one site suggests subbing for instant pudding mix, which might work.

Makes 30 filled macarons

Ingredients

The shells

140g ground almonds
125g powdered (confectioner’s) sugar
15g custard powder
100g egg white (from approx. 3 eggs), room temperature, divided 50/50
100g granulated (white) sugar
40g water
a few drops yellow gel food colouring (optional)

The filling

85g (3/4 stick) butter, room temperature
140g (1 1/4 cups) powdered (confectioner’s) sugar
20g (2 tbsp) custard powder
a few drops yellow gel food colouring (optional)

Directions

The shells

Prepare 2 parchment lined baking sheets.

Mix the ground almonds, powdered sugar and custard powder together then grind in a food processor until you have an extra fine texture.

Sift into a large bowl, re-grinding any bigger pieces of almond.

Add 50g egg whites and mix thoroughly into the almond mixture. Set aside.

In another bowl, or the bowl of a stand mixer, beat the other 50g egg whites to stiff peaks.

Meanwhile, put the granulated sugar and water into a small saucepan and heat on medium-low to 118°C (244°F).

While whisking constantly on low speed (to avoid splashing hot syrup), slowly add the cooked sugar mixture to the beaten egg whites, pouring it down the inside edge of the bowl. Whisk at high speed until the mixture is cool, about 3 minutes. The mixture should increase in volume and become firm (you should get a beak when you lift the whisk) and shiny. If you are using food colouring, add it during the final minutes of whisking.

Scrape the meringue onto the almond mixture and incorporate with a rubber or silicone spatula until you have a homogenous batter that runs from the spatula in a thick ribbon and a trail in the batter melts back into itself within 20 seconds.

Transfer the mixture into a piping bag fitted with a 7 – 9mm plain tip (this is best done in two batches, so you don’t overfill the bag). Pipe 60 equally sized rounds, about 3cm, in staggered rows onto the prepared sheets. Hold the piping bag upright with the tip just above the sheet and pipe without pulling upwards or swirling in circles, so the batter comes out in a round blob around the tip, and give a little sideways flick at the end to break the stream.

Tap the baking sheet firmly on the bench several times to release air bubbles and obtain a smooth surface. Leave the tray to rest at room temperature for at least 20 minutes until a slight skin forms.

Meanwhile, preheat oven to 150°C (300°F).

Bake the macarons for 20 minutes, one sheet at a time, turning the sheet half-way.

Remove from oven and remove the parchment from the tray with the shells still on it and place on a cooling rack for at least 30 minutes, until completely cool, then remove macaron shells carefully from the parchment.

The filling

Using a wooden spoon or an electric mixer, beat butter (and food colouring, if using) until pale and fluffy. Whisk together icing sugar and custard powder and add to butter in two or three batches, beating continuously, until you have a smooth frosting.

Pipe or spoon a generous blob of filling onto the flat side of half the shells, top with the remaining shells and press gently until the filling reaches the edges.

Store in an airtight container in the fridge to mature for at least 24 hours before eating.