Cognac and Tonic Browse more: Recipes Ingredients CognacTonic waterLemon, thinly sliced Steps Mix two to three parts tonic water with one part Cognac. Serve over ice in a snifter with a slice of lemon. Previous recipe: Coffee with Baileys and Frangelico Next recipe: Cognac-Glazed Dried Apricots with Cinnamon-Spiced Yogurt