Sauté the onions in oil until they become clear.

Add the carrots to the sautéed onions.

Continue to sauté the carrots until they soften.

Incorporate the flour into the mixture and stir well to combine.

Introduce the chopped tomatoes and tomato paste (or the contents of a small can of tomato paste) to the pan.

Stir the ingredients together to ensure they are well mixed.

Pour enough water into the skillet to fill it, leaving some space for stirring without spillage.

Add parsley, salt, pepper, and basil to taste, adjusting the seasoning according to your preference.

Allow the sauce to simmer until it thickens to your desired consistency.