Heavy whipping cream differs from whipped cream. The latter you prepare in seconds with a mixer using the former. Commercially sold milk undergoes pasteurization and homogenization processes which render the fats incapable from separating from the milk. To make your own homemade heavy whipping cream, you must have access to raw milk straight from the cow. Inquire at a local dairy or farmers' market for the raw milk if you do not have a cow.
Pour the raw milk into the baking pan and let sit in the refrigerator for 24 hours to allow the milk and cream to separate.
Gently ladle the top layer of heavy whipping cream from the baking pan and transfer to the pint jar.
Refrigerate the heavy whipping cream in the sealed pint jar until ready to use, up to 2 days.
Place the mixing bowl and whisk attachment in the mixer into the freezer for 15 minutes to chill.
Pour 1 cup of the chilled heavy whipping cream into the cold mixing bowl.
Secure the whisk attachment to the mixer and mix the whipping cream on low speed. Slowly increase the speed to high to whip the heavy cream.
With the mixer whisking the cream on high speed, add in 1 tbsp. sugar and 1/2 tsp. vanilla extract. Continue to beat until stiff peaks remain standing up on the end of the whisk when removed from the cream. Expect a yield of 2 cups of whipped cream from 1 cup of liquid heavy whipping cream.
Use the stiffly beaten whipped cream as a dessert topping or mixed into recipes immediately as time and exposure to heat will cause it to deflate.