Sweet Potato Casserole with Marshmallows

Ingredients (9)

• 2 pounds sweet potatoes, peeled and cubed
• 1/4 cup unsalted butter, softened
• 1/4 cup brown sugar
• 1/2 teaspoon cinnamon
• 1/2 teaspoon crushed red pepper, optional
• 1 teaspoon kosher salt, to taste
• Black pepper, to taste
• 1/2 cup chopped pecans, divided
• 1 1/2 cups mini marshmallows