Stir the milk, vanilla, and cinnamon together in a medium-sized bowl. Using a stand mixer with a whisk attachment, beat the cream on high for 3 minutes, until you get stiff peaks.
Fold the whipped cream into the milk mixture. Then, stir in 1 ¼ cups of snickerdoodles.
Pour the mixture into a loaf pan, smooth the top with a spatula, and sprinkle the rest of the cookie bits over the top. Cover with plastic wrap and freeze for about 6 hours, then scoop and enjoy!