Batch Whiskey Sour

 Make a Swiss meringue with 4 egg whites, 100g sugar, 1/4 tsp cream of tartar, 1/4 tsp kosher salt. Mix everything in a metal bowl and heat over a double boiler whisking constantly until the mixture reaches 175F. Remove from heat and whisk until soft to medium peaks. I used a hand mixer but a stand mixer is probably better.

Make lemon simple syrup with 8 oz water, 4 oz granulated sugar, strips of lemon peel from 3-6 lemons. Heat over medium heat until sugar is melted. Reduce to low and simmer for 10 minutes. Turn off heat and let cool.

Mix 6 ounces of simple syrup, 6 ounces of lemon juice and 12 once of bourbon.

To make a glass mix a few tablespoons of meringue with 3 to 4 ounces of bourbon mixture. Stir until meringue is foamy. Add ice and stir until chilled. Top with a few drops of aromatic bitters.