Peel onions and wash them under water. Combine vinegar and water in measuring jar. Set it aside.

Using a knife make a cross on the onions.

I prefer to use beets as my food coloring. You can use beets in any form - freshly sliced, dried beets or powdered beets powdered.

My favorite is beets powder. I make it at home by drying beets in a warm oven (200 degree F) for 8 hours, then ground it to its powdered form.

Add beets powder to vinegar + water. For a deep garnet color I have added 1.5 teaspoon of beets powder to vinegar.

Whisk until well combined. Add sugar and salt.

Get your onions ready.

Storing for longer time - add onions to a bowl. Pour vinegar and allow the onions to sit in this solution for 1-2 hours. But if using onion rings (onion cut in circles) then soak them for not more than 30-40 minutes.

After the desired soaking time, onions will have a light red color.

For a rich garnet red color - add onions to a jar. Pour vinegar and beets mix to the jar until onions are fully drenched in this solution.

Close the lid and store onions in the refrigerator overnight. Whole onions stay crispy for long.

Once marinated for the desired amount of time, remove onions from the solution, discard the liquid and store onions an airtight glass container. Onions can be stored in the refrigerator for up to 2 weeks.