Smoked mackerel, egg and creamy spiced slaw sandwich recipe

Ingredients

• 75g cabbage, shredded
• 75g carrot, grated or julienned
• 1/4 small red onion, very finely sliced
• 1 red chilli, halved, deseeded and finely shredded
• 60g mayonnaise
• 30g Greek yogurt
• 1 tsp curry paste, or as needed
• 4 slices rye sourdough
• Butter, at room temperature (optional)
• 110g smoked mackerel, skin removed, flesh broken into pieces
• 4 tsp mango chutney (optional)
• 1 large hard-boiled egg (or 2 small ones), sliced
• 1 tbsp mayonnaise
• Generous shake of Tabasco