Summertime Beetroot and Rocket Veggie Rolls with Tomato Relish - Kathryn Bruton Food & Drink

Ingredients

• 1 red onion
• 2 tbsp olive oil
• 1 tsp mustard seeds
• 1/2 tsp fennel seeds
• 1/2 tbsp soft dark brown sugar
• 450g vine tomatoes
• 3 tbsp red wine vinegar
• 500g good quality vegetarian haggis
• 1 large beetroot, peeled and grated
• 30g rocket, finely chopped
• 375g block of all butter puff pastry
• 1 tbsp black sesame seeds to garnish
• 1 egg
• salt and pepper