Mix yeast into warm milk and leave for 10 minutes until foamy.
Knead flour, sugar, salt, milk mixture, and eggs in a food processor for 5 minutes.
Gradually knead in softened butter a teaspoon at a time over 10 minutes.
Knead with extra flour until smooth, then let rise in a greased bowl for 1.5 hours.
Preheat the oven to 180°C.
Knock back dough, shape into 6 rolls, and prove for 45 minutes.
Season lamb mince, shape into 4 patties, and chill for one hour.
Brush rolls with egg yolk and bake for 15-20 minutes until golden.
Blend yolks, vinegar, and mustard, then slowly drizzle in oil and stir in mint.
Sauté shallots, tomatoes, and garlic in oil, then simmer with vinegar and sugar.
Fry lamb patties in oil for 2-3 minutes per side and rest.
Heat deep-frying oil to 180°C.
Fry potato chips for 3-4 minutes until crisp and season with salt.
Assemble halved toasted buns with chutney, burger, gherkins, vegetables, and mint mayonnaise.