Ingredients

For the Vanilla Ice Cream Base

• Glucose syrup (5%) 50g | ¼ cup
• Brown Sugar (15%) 150g | ¾ cup
• Cream (30%) 300g | 1 ½ cups
• Milk (40%) 400g | 2 cups
• Egg yolks (10%) 100g | about 4 large yolks
• Cornstarch 10g | 1 tablespoon plus 1 teaspoon, mixed with 40g | 4 tablespoons of cold milk
• Creme Fraîche 100 g
• Vanilla paste 1 Tbsp
• Dark Rum 60g | 4 tbsp

For the Chocolate Swirl (Stracciatella)

• Dark Chocolate 100g
• Kosher or sea salt 3g | ½ teaspoon
• Cream 50g | ¼ cup

For the Peanut Butter Swirl

• Creamy peanut butter 250g | 1 cup
• Coconut oil 45g | ¼ cup
• Sea Salt 5g | 1 tsp

Instructions

For the Ice Cream Base

1. Prepare an ice bath. Fill a large bowl two-thirds of the way with very icy ice water and place it in the refrigerator.
2. Boil the dairy and sugars. Put the cream, milk, glucose, and sugar in a medium heavy-bottomed saucepan, and place it over medium-high heat. Cook, whisking occasionally to discourage the milk from scorching, until the mixture comes to a full rolling boil. Whisk into the simmering dairy the cornstarch mixture and then cook for 1 minute.  Then remove the pot from heat.
3. Temper the yolks and cook the custard. In a medium bowl, whisk the yolks. Add ½ cup of the hot dairy mixture to the yolks while whisking so the hot milk doesn’t scramble the yolks. Pour the tempered yolks back into the pot of hot milk while whisking. Place the pot over medium-low heat and cook, stirring and scraping the bottom of the pot constantly with a rubber spatula to avoid curdling. Once the eggs have been tempered whisk in to the base the banana purée.
4. Chill. When you notice the custard thickening, or the temperature reaches 180°F on a kitchen thermometer, immediately pour the custard into a shallow metal or glass bowl. Nest the hot bowl into the ice bath, stirring occasionally until it cools down.
5. Strain. Strain it through a fine-mesh sieve to remove any bits of egg yolk. Then add the creme fraîche and the vanilla paste. Mix the custard with the inversion mixture until completely mixed.
6. Cure. Transfer the cooled base to the refrigerator to cure for 4 hours, or preferably overnight.
7. Whisk. Prior to churning the ice cream base, stir in the dark rum. Taste and adjust accordingly.
8. Churn. Place the base into the bow] of an ice cream maker and churn according to the manufacturer’s instructions. The ice cream is ready when it thickens into the texture of soft-serve ice cream and holds its shape, typically 20 to 30 minutes.
9. Add the Chocolate Swirl and Peanut Butter Swirl. When the ice cream is about 5 minutes from completion, start slowly pouring into the ice cream maker the chocolate swirl and the peanut butter swirl as separate swirls. Add these slowly so it will harden as it mixes and not get integrated into the ice cream base. You will need to redirect the ice cream base away from the edge of the maker so it gets integrated to the entire ice cream and not just on the edges.
10. Harden. To freeze your custard ice cream in the American hard-pack style, immediately transfer it to a container with an airtight lid. Press plastic wrap directly on the surface of the ice cream to prevent ice crystals from forming, cover, and store it in your freezer until it hardens completely, between 4 and 12 hours. Or, feel free to enjoy your ice cream immediately; the texture will be similar to soft-serve.

For the Chocolate Swirl (Stracciatella)

1. Melt the ingredients. Place the dark chocolate, milk chocolate, cocoa powder, salt and cream in the top of a Bonne Marie pot.
2. Fill the bottom of the Bonne Marie pot with 2 inches of water. Place the pot over high heat and cook until it comes to a boil, then reduce the heat to a simmer. Nest the top bowl of chocolate over the pot of simmering water, and melt the chocolates, stirring occasionally, until smooth. Remove the bowl from the pot, wipe the bottom dry of any condensation, and set aside in a warm place.
3. Store the chocolate swirl. Remove the bowl from the Bonne Marie, and let it cool to room temperature. Store the chocolate swirl in an airtight container in your cupboard.
4. To use the chocolate swirl in your ice cream, heat it just enough that it is fluid but not hot. This should be about 60°F.

For the Peanut Butter Swirl

1. Melt the ingredients. Place the peanut butter, coconut oil, and salt in the top of a Bonne Marie pot.
2. Fill the bottom of the Bonne Marie pot with 2 inches of water. Place the pot over high heat and cook until it comes to a boil, then reduce the heat to a simmer. Nest the top bowl of peanut butter over the pot of simmering water, and melt the peanut butter and coconut oil over this water bath and mix until fully combined.
3. Store the ribbon. Remove the bowl from the Bonne Marie, and let it cool to room temperature. Store the peanut butter swirl in an airtight container in your cupboard.
4. To use the peanut butter ribbon in your ice cream, heat it just enough that it is fluid but not hot. This should be about 60°F.