The day before you want to bake your macarons, prepare the yuzu cream. Start by cubing the butter, then allowing it to reach room temperature. Mix together the yuzu zest and sugar in a pan. Next, stir in the cornstarch, egg, and yuzu juice.
Warm over a low heat, stirring, until the mixture thickens. Set to one side and allow to cool before stirring in the butter. You want the butter to be evenly mixed, so if you have a whisk blender it may be easiest to use it. Leave the mixture to refrigerate overnight.
In one bowl sift together the powdered sugar and almond flour. In another bowl whisk together the egg whites. Slowly add the regular sugar to the egg whites, whisking until they form soft peaks. Next, gently fold in the sugar and flour mixture from the first bowl, along with your food colouring. Try not to use a metal utensil for this step and be quite gentle, otherwise your macarons may not puff up as nicely as they could.
Preheat your oven to around 150C and prepare a baking tray with greaseproof paper. Using a piping bag, pipe a matching number of circles on the paper. Don’t make the circles too close together, the batter will spread and you may end up with your halves sticking together.
Tap the sheet on your counter to remove any air bubbles and leave to sit for 10 minutes, until a film begins to form on top of the macarons. Next bake the macarons for around 15 minutes.
Leave the macarons to cool until they can be easily removed from the paper. Next, turn them over and pipe the yuzu cream into both halves, before carefully sandwiching them together.
• If you want to make your macarons heart shaped, simply pipe a v-shape instead of a circular blob. If you leave them to sit and they’ve spread and got a bit un-hearty, use a tooth pick to make a little dent down the middle and hopefully they should get more heart-esque after cooking.