Peel the beetroot and cut into slices. Wash thyme and shake dry. Spread beetroot on a baking tray lined with baking paper. Drizzle with olive oil, season with salt and pepper. Spread thyme on top. Cook in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: see manufacturer) for approx. 30 minutes
For the dip, clean and wash the spring onions. Cut 1 spring onion into fine rings. Cut the remaining spring onions into pieces of about 4 cm length. Mix sour cream and spring onion rings. Season to taste with salt and pepper
Meanwhile, wash the lemon hot, grate dry and cut into slices. Dab meat dry. Season with salt and pepper. Heat oil in a pan. Brown the meat on both sides for about 2 minutes, remove. Place the meat, spring onions and lemon on the baking tray approx. 10 minutes before the end of the cooking time. Cook meat in the oven for approx. 5 minutes, take it out of the oven again. Cover lightly with aluminium foil and leave to rest for about 5 minutes. Arrange meat and vegetables on a plate. Add dip