Chocolate and chilli tart

Base

• 50 g caster sugar
• 50 g brown sugar
• 80 g unsalted butter, cut into pieces
• 1 pinch sea salt
• 1 egg
• 150 g plain flour
• 40 g cocoa powder

Chocolate mousse filling

• 300 g thickened cream, plus extra to serve (optional)
• 180 g dark chocolate (minimum 70% cocoa), broken into small pieces
• 180 g milk chocolate, broken into small pieces
• 50 g water
• 1 tsp natural vanilla extract
• ½ tsp ground cinnamon
• ¾ - 1 tsp chilli powder, to taste
• salted pretzels, to decorate