Soft Creamy Chocolate Mousse Cake

Chocolate mousse cake recipe * Chocolate sponge (40 x 25.5 cm or 15 x 10 in pan); finished cake: 16 cm / 6in square pan - 1 cup = 236ml 3 egg white 60g sugar (1/4 cup 1/2 tbsp) 25g cocoa powder (1/4cup) 45g hot water (3tbsp) 50g cake flour (1/2 cup - 1 tbsp) 3 egg yolks 20g sugar (1.5 tbsp) 20g vegetable oil () * Chocolate mousse 70g dark chocolate - chopped () 2 egg yolks 30g sugar (2.5 tbsp) 100g warm milk (1/2 cup) 1 tsp instant coffee gelatine sheet x 3 250g heavy cream - soft peaks (1 cup) 15g sugar (1 tbsp) * The chocolate glaze 70g cocoa powder (3/4 cup) 120g hot water (1/2 cup) 120g heavy cream (1/2 cup) 160g sugar (3/4 cup) gelatine sheet x 3 white chocolate and strawberries for garnishing Kitchenware (Amazon affiliate links) Digital food scale: Square cake ring (6in / 16cm): Reusable parchment baking sh