1 tsp garlic powder
1 large gherkin, finely chopped
squeeze lemon juice
2 tbsp tomato ketchup
100²µ/3½´Ç³ú mayonnaise
flaked sea salt and freshly ground black pepper
½ tsp chipotle paste or other hot sauce
800g/1lb 12oz chuck steak, minced
50²µ/1¾´Ç³ú bone marrow, finely diced