Mello Yello® Recipe

Make simple syrup (if using)

If using homemade simple syrup instead of HFCS, combine 1 cup granulated sugar with 1 cup water in a small saucepan. Heat over medium, stirring until sugar dissolves. Remove from heat and cool to room temperature. Chill before using.

Prepare citric acid solution

Dissolve 1/2 teaspoon citric acid powder into 1 tablespoon warm water to create a concentrated citric acid solution. This helps distribute the acid evenly in the syrup.

Blend flavor base

In a medium heatproof bowl or measuring cup, combine the 1 cup sweetener (HFCS or chilled simple syrup), the 1 teaspoon lemon extract, 1 teaspoon orange extract, and 1 teaspoon vanilla extract. Stir thoroughly until uniform.

Add citric acid and optional caffeine/color

Stir the 1 tablespoon citric acid solution into the flavor base. If using caffeine, dissolve the measured 50 mg food-grade caffeine powder into a teaspoon of warm water first, then mix into the flavor base. Add the yellow food coloring a few drops at a time until you reach a bright mellow-yellow hue.

Combine with carbonated water

Chill the carbonated water well. Gently pour the 10 cups chilled carbonated water into a large pitcher. Slowly add the prepared flavor syrup mixture to the carbonated water while stirring very gently with a long spoon to avoid dissipating carbonation. Taste and adjust: add up to another 1-2 tablespoons sweetener if you prefer sweeter soda, or a pinch more citric acid solution for brighter acidity.

Chill and rest

Refrigerate the assembled soda for at least 30 minutes to allow flavors to marry while retaining carbonation. Serve cold.

Fill a tall glass with ice cubes (about 3–4). Pour chilled Mello Yello over the ice, leaving a little headspace. Garnish with a lemon wheel or wedge on the rim. Serve immediately with a straw.