Add the heavy whipping cream and food coloring to a deep mixing bowl. Using a hand mixer or stand mixer, beat at high speed for about 4-5 minutes, or until stiff peaks form and the cream is light and fluffy. (It should resemble whipped cream.)
3 cups heavy whipping cream, 2 Tbsp royal blue food coloring, optional
Continue adding drops of food coloring, until the whipped cream reaches the desired blue color.
Add the condensed milk and vanilla paste to the whipped cream. Mix at low speed just until fully combined and smooth. (Taste the mixture and if you prefer a sweeter ice cream, mix in a little more condensed milk.)
3/4 cup condensed milk, 1 1/2 Tbsp vanilla bean paste, or vanilla extract
Pour about 1/3 of the vanilla ice cream mixture into an ice cream container, loaf pan, or metal bread pan.
Add some crushed cookies and oreos over the ice cream and mix to spread it throughout.
Repeat the layering process 2–3 more times until all the ice cream mixture has been used. Smooth the top layer with a spatula, then top with the remaining crushed cookies and Oreos.
Press a piece of parchment paper or plastic wrap directly onto the surface of the ice cream to help prevent ice crystals and freezer burn, then cover tightly with a lid or foil.
Freeze for at least 8-12 hours, or overnight, until the ice cream is fully firm and scoopable.
When ready to serve, let the cookie monster ice cream sit at room temperature for 4–5 minutes to soften slightly. Scoop into bowls or cones and enjoy. (For easier scooping, dip your ice cream scoop into hot water and wipe it dry before each scoop.)