In a bowl with 50 g egg whites add food coloring, stir and pour over almonds mixture.

Place the other 50 g of egg whites into a mixer bowl. Set aside until you prepare the sugar syrup.

In a small sauce pan combine caster sugar with water and place on medium heat. Using a candy thermometer measure syrup temperature. When it reaches 230 F (112C) start whipping the egg whites. When the syrup hits 244F (118C) pour it over the whipped egg whites while mixing continuously. Continue beating until the bowl has cooled slightly, and glossy stiff have formed.

Add the whipped whites over the almonds mixture and using a rubber spatula gently fold in until combined and smooth. Work the batter until it flows in very thick ribbons when the spatula is lifted.

Transfer the mixture to the piping bag fitted with a 1/2 inch (1 cm) plain tip. On one sheet, following the drawn circle, pipe a disk of batter in a spiral, filling the  whole circle. On the other sheet pipe a ring following the drawn circle (about 1 inch), which will be the border of the cake.

Bake in the preheated oven for 25-30 minutes. Remove from oven and allow to cool. Do not remove the macaron ring from baking sheet while still warm as it will break.

While the macaron disk and ring are baking prepare the pistachio cream filling. In a sauce pan bring milk to a simmer.

Whisk egg yolks with sugar until light yellow. Add cornstarch.

Pour a third of the hot milk over the yolks mixture and pour the whole mixture back into the pan. Bring to a boil while stirring with a whisk. Remove from heat and let cool for 10 minutes and then incorporate half of the butter. Cover with plastic wrap and allow to cool.

Meanwhile chop the raw pistachios. Wash the strawberries, drain and cut in halves.

 In a large bowl whip the cooled cream with an electric mixer. Add the other half of butter and pistachio paste, whip until smooth. Fold in chopped pistachios.