Grand Big Mac

Ingredients

• 300g mayonnaise
• 1 tbsp onion chutney or relish
• 2 tsp white vinegar
• 2 tsp yellow mustard
• 1/2 tsp white pepper
• 1 tsp onion powder
• 1 tsp garlic powder
• 1 tsp smoked paprika
• 500g beef mince
• 2 tbsp olive oil
• 2 sesame burger buns (I used mixed seed brioche buns)
• 1/2 white onion, finely chopped
• 2 handfuls iceberg lettuce, chopped
• 2 slices cheese
• Few slices of gherkins