In a medium bowl, place and microwave your cream cheese for 5-10 seconds to soften up if it was in the fridge so that it can mix well with other ingredients.
Mix your cream cheese with 1 tsp lime extract and 1/3 cup granulated sugar and whisk until thoroughly mixed.
Gently whisk in 1 cup of whole milk and 3/4 cup heavy cream.
Go in with 2 tbsp key west lime juice and whisk.
Add food coloring (green and yellow) to enhance the color and have a more lime-like appearance(optional)
Pour your mixture into a Ninja Creami pint container. Make sure not to fill past the max fill line.
Ensure it is placed on a flat surface and freeze pint for 24 hours.
Remove from the freezer after 24 hours, and plug in your Ninja Creami.
Following the Ninja Creami instructions, secure your bowl into the machine, and press the "Ice Cream" button.
When the creaming process is finished, remove the pint from the machine, create a hole in your treat, and drop in the crushed graham crackers.
Return the pint to the Ninja Creami machine and select "Mix-in."
Your treat is ready; enjoy!