Salt and Straw (Chocolate Brownie)

https://www.youtube.com/watch?v=c9YIv-4SfPw&t=43s

1. Prepare the base: Combine the milk, sugar, corn syrup, dry milk and xanthan gum in a medium pot and stir to combine. Set the pot over medium heat and cook, stirring often until the sugar has dissolved, about 3 minutes. Remove from heat.
2. Add the cream and whisk until fully combined. Transfer the mixture to an airtight container and refrigerate until chilled. (For best flavor, chill for about 12 hours.) The base can be stored in the refrigerator for up to 1 week or in the freezer for up to 3 months. If frozen, be sure to thaw fully before using.
3. As ice cream chills, prepare the brownies: Heat the oven to 350 degrees. Line a 9x9-inch baking dish with parchment paper and coat with nonstick spray.
4. Assemble a double boiler by placing a small saucepan filled with an inch of water over medium heat and bring to a simmer. Place the butter and chocolate in a medium heatproof bowl and set it on top of the saucepan (make sure the bottom of the bowl does not touch the water). Reduce heat to low, and stir the butter and chocolate until fully melted together. Remove the double boiler from heat and set aside.
5. In a stand mixer fitted with the paddle attachment or with an electric hand mixer, beat the eggs and sugar until light and frothy, about 3 minutes. Reduce the speed to low and stream in the chocolate mixture. Increase the speed to medium-high and mix until well combined.
6. In a separate bowl, whisk together the flour, cocoa powder and salt. Add the flour mixture to the chocolate mixture and mix on low until just combined. With the mixer running, drizzle in the heavy cream and mix until just combined, scraping down the sides as necessary. Fold the Marshmallow Fluff into the batter with a spatula or large spoon, mixing just enough to get most of it incorporated with a few streaks remaining.
7. Pour the batter into the prepared baking dish and spread into an even layer. Bake about 30 minutes, until the top is crackly and a knife inserted into the center comes out clean. Let them cool completely and cut into 1/2-inch pieces. Freeze in sealed freezer bags before using; they will keep up to 2 months.
8. Once ice cream base is chilled, mix in the flavoring: Combine the sugar and 1/4 cup water in a small saucepan, set it over medium heat and bring to a boil. Remove from the heat and whisk in the cocoa powder until it is smooth and glossy. Let cool to room temperature.
9. Pour the chocolate syrup into the chilled ice cream base and whisk to combine. You may want to refrigerate this mixture until cold if your base was not chilled ahead of time, or if using a pre-frozen bowl machine.
10. Pour the mixture into an ice cream maker and churn, according to your machine’s instructions, until it has the texture of soft serve.
11. When churned, layer the ice cream and brownies in a freezer-friendly container. Cover with parchment paper and freeze until firm, about 6 hours. The ice cream will keep up to 3 months.
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Mixi In (Brownies):
1/2 cup/115 grams unsalted butter (1 stick), cut into 1-inch chunks
3/4 cup/130 grams chocolate chips (5 ounces)
2 large eggs
3/4 cup/150 grams granulated sugar
1/2 cup/65 grams all-purpose flour
1/4 cup/25 grams unsweetened cocoa powder, preferably Dutch-processed
2 teaspoons kosher salt
1/2 cup/120 milliliters heavy cream
1 cup/240 milliliters Marshmallow Fluff
FOR THE CHOCOLATE FLAVOR:
1/4 cup granulated sugar

1/4 cup water
1/4 cup unsweetened cocoa powder