Almond, Chocolate, and Pistachio Spumoni

INGREDIENTS

• 6 cups whole milk
• 1/2 teaspoon pure almond extract
• 1 teaspoon pure vanilla extract, divided
• 1/2 cup unsweetened cocoa powder (not Dutch-process)
• 1 1/4 cups sugar
• 1/2 cup unsalted shelled pistachios, toasted and coarsely chopped
• 2 drops green food coloring
• 1/2 cup cornstarch
• 8 large egg yolks
• 2/3 cup whole blanched almonds, and coarsely chopped