Combine ¼ cup sugar and 2 tablespoons of cornstarch in heavy bottomed saucepan over medium heat. Whisk egg and milk together. Gradually add milk mixture to sugar mixture and bring to a boil, stirring constantly. Cook for 1 minute while continuing to stir.
Combine pumpkin, pumpkin flavor extract, cinnamon, salt, and nutmeg. Slowly add pumpkin mixture to milk mixture, whisking constantly. Cook over low heat, continuing to stir for 3 minutes. Do not boil.
Divide pudding evenly between 4 pudding dessert dishes. Cover surface of pudding with plastic wrap to prevent pudding from forming a skin. Chill.
When ready to serve, place cream in a bowl with 2 tablespoons of sugar. Beat with a mixer until stiff peaks form. Top each serving with 2 tablespoons whipped topping and ½ tablespoon peanut brittle pieces.