Put sugar and 1 tablespoon water in a saucepan and let caramelize over medium heat while stirring. Add 125 ml each of white wine and water and deglaze the caramel with it, then reduce the liquid by half.
Remove a twig from the basil and put it in water first. Place the basil in the hot stock and let it steep for at least 1/2 hour. Then remove and pour another 125 ml of white wine.
Put the apricot cubes with the apricot liqueur in a suitable container and let it steep overnight.
The next day, place in a punch bowl and add the fresh sprig of basil and half of the basil-wine mixture. Mix everything well and season with basil if necessary. If necessary, add the remaining basil-wine mixture.