Melt 4 oz white chocolate candy melts in the microwave according to package instructions (heat in short bursts, stirring between bursts until smooth).
Place 2 cups Cinnamon Toast Crunch cereal in a large bowl. Pour the melted white chocolate over the cereal and stir gently until the cereal is evenly coated.
Spread the coated cereal in a single layer on the prepared wax paper. Arrange individual pieces so they do not stick together. Let cool on the counter until the chocolate is set and firm (about 10–20 minutes).
Once set, break the coated cereal into bite-size pieces. If you prefer some pieces for garnish, set aside a small handful before folding into the ice cream base.
In the bowl of a stand mixer (or a large bowl using a hand mixer), beat 8 oz softened cream cheese on medium speed until light and fluffy, about 2–3 minutes.
Add 8 oz thawed Cool Whip, the 114 oz can sweetened condensed milk, 1 tsp vanilla extract, and 1/2 tsp cinnamon to the bowl. Beat on low to medium speed until the mixture is smooth and fully combined, about 1–2 minutes. Scrape the bowl as needed.
Gently fold the broken, candy-coated cereal pieces into the cream cheese mixture until evenly distributed. Hold back any pieces reserved for topping, if desired.
Transfer the mixture to a freezable container (a loaf pan works well). Smooth the top with a spatula and sprinkle any reserved coated cereal pieces over the surface, if using. Cover tightly.
Freeze for at least 4 hours, or until firm. Remove from freezer a few minutes before scooping if desired, then serve.
Notes
10. Freeze for at least 4 hours, or until firm. Remove from freezer a few minutes before scooping if desired, then serve.