Beetroot Burgers from Simple Food by Jill Dupleix

Ingredients

• 500 g minced beef
• 3 tbsp. pickled beetroot, finely chopped
• 1 tbsp olive oil
• 1 tbsp pickled beetroot juice
• freshly ground black pepper
• 4 English muffins
• 1 onion, peeled
• 1 tbsp butter
• sea salt
• 1 tbsp capers, rinsed and chopped
• 2 egg yolks