Almond Croissant

Name: Almond Croissant
Ingredients: 60 g ground almonds; 115 g confectioner's sugar; 15 g corn starch (or all purpose non bleached flour); 90 g unsalted butter (softened, tempered to room temperature); 50 g egg; 1/4 tsp pure vanilla extract; pinch fine sea salt; 300 g mandarin (or clementines); 90 g granulated sugar; 6 g pectin; 250 g filtered water; 100 g granulated sugar; 20 g confectioner's sugar; 20 g ground almonds; 1 tsp pure vanilla extract; 1 1/2 tsp orange blossom water (or one clementine zest); 10 croissants (ideally 1-2 days old)