Roasted Frozen Sweet Potatoes With Whipped Crème Fraîche and Granola

Ingredients (9)

• 4 sweet potatoes (about 1 pound; 450g each), scrubbed (see note)
• 1 cup (240ml) heavy cream
• 1/4 cup (60g) creme fraiche
• 4 teaspoons (15g) confectioners' sugar
• 1/2 teaspoon vanilla extract
• Pinch ground ginger
• Pinch ground cinnamon
• Pinch kosher salt
• Homemade or store-bought granola, for topping