Chocolate Pie - Fill Your Plate

Ingredients

• 1 whole pie crust, baked and cooled (or can use Oreo or graham cracker crust)
• 1 1/2 c. sugar
• 1/4 c. cornstarch
• 1/4 tsp. salt
• 3 c. whole milk
• 4 whole egg yolks
• 6 1/2 oz. weight bittersweet chocolate, chopped finely
• 2 tsp. vanilla extract
• 2 tbsp. butter
• Whipped cream, for serving