First, prepare your whipped cream. Place your stand mixer bowl and whisk attachment in the freezer for about 15 minutes prior to starting. This will ensure they're extra cold for your homemade cake batter whipped cream.
Once thoroughly chilled, place the 2 cups of the heavy cream into the mixer bowl and begin whipping on HIGH speed for about 4-5 minutes or until soft peaks form. Sprinkle in the cup of dry, powdered cake mix and continue beating on HIGH for an additional 2 minutes or until stiff peaks have been achieved. Sprinkle in some rainbow jimmies to combine. Set mixture aside in fridge.
In a large bowl, whisk together the two boxes of pudding mix, the almond extract and the 2 cups of cold milk. Mixture will be thick. Stir in a handful of rainbow sprinkles. Fold HALF of the whipped cream into the pudding mixture until combined; spread evenly and carefully into the prepared pie crust. Top with remaining whipped cream.
Refrigerate the pie for at LEAST 2 hours or until set, before cutting into slices. Store leftovers in the fridge covered for up to 2 days.