You need 1 ingredient. The key ingredients include: ["Prepare the three gelati flavors", "Apple Gelato:", "1/4 cup white sugar", "1/8 cup lemon juice", "3 cups granny smith apples, peel on, cut into 1/2-1"" chunks (seeds and cores discarded)", "1 cup heavy cream", "2 cups milk", "1/2 cup sugar", "1/4 teaspoon dried thyme, rubbed between fingers", "12 large egg yolks", "1/2 cup corn syrup", "1/4 teaspoon kosher salt", "1/4 teaspoon vanilla extract", "Celery Gelato:", "14 ounces peeled celery and leaves,cut into 2"" pieces(light green stalks often don't need peeling)", "water", "1 1/3 cups celery juice from above celery", "5 star anise, pulled apart", "2 cups whole milk", "1 cup heavy cream", "1/4 cup sugar", "3 tablespoons corn syrup*", "5 large egg yolks", "1-3 tablespoons green tea powder(1 Tablespoon for color; 2-3 Tablespoons for stronger green tea flavor)", "EVOO Gelato:", "1/2 cup sugar", "1/2 tablespoon lemon zest (microplane is best)", "1 teaspoon lemon juice", "1/2 cup water", "3 tablespoons corn syrup", "3 large eggs", "2 large egg yolks", "3/4 cup fruity extra virgin olive oil (not grassy or bitter)", "1/4 teaspoon kosher salt", "3/4 cup whole milk", "Prepare the Apple Chips and Candied Walnuts; Assemble", "4 crisp hard red skinned apples, skin-on, sliced into thin rounds and dipped in lemon juice to keep from browning", "1 cup water", "1 1/2 cups sugar", "2 star anise, broken up", "2 cups sugar syrup from apple chips", "1 cup walnut halves", "2 lemons' lemon juice", "1 cup celery shavings(taken after tough stringy outer layer has been peeled)", "4 2-3"" high wispy celery sprigs with leaves"].