Peel and grate the beetroot and fry in a little olive oil.
Cut the onions into fine rings and fry them in a separate pan in olive oil. Peel and grate the carrots and mix with the onions in the pan, continue cooking for approx. 5 minutes.
Mix the vinegar, sugar, salt, tomato paste and pepper in a large saucepan, add the beetroot and the onion / carrot mixture and simmer on a low flame for 10 minutes, season to taste.
Pour into prepared sterilized jars.
Preheat the oven to 80 degrees, place the open glasses in a deep pan with water and place in the oven for 30 minutes. Then close the jars tightly.