Banana Bread, But Make It a Layered, Crowd-Pleasing Showstopper

Ingredients (21)

• 1 1/2 cups (355 ml) whole milk
• 3 large egg yolks
• 1 large egg
• 120 g light brown sugar (4 ounces; 1/2 cup packed) 
• 16 g all-purpose flour (about 1/2 ounce; 2 tablespoons)
• 8 g cornstarch (about 1/4 ounce; 1 tablespoon) 
• 1/2 teaspoon Diamond Crystal kosher salt; for table salt, use half as much by volume
• 3 tablespoons cold unsalted butter (about 42 g, 1 1/2 ounces), cubed
• 1 tablespoon (15 ml) vanilla extract
• 6 very ripe bananas (2 pounds; 907 g total), peeled and cut crosswise into 1/2-inch thick slices
• 213 g light brown sugar (7 1/2 ounces; 1 cup packed)
• 8 tablespoons unsalted butter (about 4 ounces; 112 g), cubed
• 1/2 teaspoon ground cinnamon
• 1/2 teaspoon Diamond Crystal kosher salt; for table salt, use half as much by volume
• 2 teaspoons vanilla extract
• 2 1/2 cups (590 ml) heavy whipping cream, cold
• 38 g granulated sugar (about 1 1/3 ounces; 2 1/2 tablespoons) 
• 2 teaspoons vanilla extract
• 8 cups cubed ( 1 1/2 to 2-inch pieces) homemade or store-bought banana bread (2 pounds; 907 g; see notes)
• 95 g roughly crushed gingersnap cookies (3 1/3 ounces; 1 cup)
• Roughly chopped toasted pecans, for serving, optional