Preheat standard oven to 300°F. Oil and flour a 9x13-inch pan.
Prepare the Sweet Cream Cake Mix according to package directions. Pour batter into prepared pan; bake until a toothpick comes out clean.
Remove from oven and let cool, then cut cake into ½” cubes.
To prepare whipped topping, In a medium mixing bowl combine heavy whipping cream, vanilla, powdered sugar and cream of tartar. Whip on high speed until stiff and fluffy.
In a parfait glass, assemble the dessert as follows:
- Pour 1-2 tbsp. strawberry puree on bottom of 16 oz. parfait glass
- Layer 5-6 strawberry slices
- Add 2-3 tbsp. whipped topping
- Finish layer with 4-5 cubes of cake
Repeat steps twice, ending with whipped topping for the top layer. Garnish with a strawberry half and a sprig of mint. Chill until ready to serve.