Soften 1 tbsp cream cheese in microwave for 5-10 seconds.
Combine cream cheese, 1 tsp vanilla, 1/3 cup sugar, cocoa, and salt.
Gradually whisk in 1 cup milk and 3/4 cup cream.
Add 35 drops of red food coloring, mix until desired color.
Pour mixture into Ninja Creami pint, below max fill.
Freeze pint flat for 24 hours.
Remove pint, prepare Ninja Creami machine.
Secure pint in outer bowl, cover, lock into machine.
Press "Ice Cream" button and wait for result.
Remove pint and outer bowl from machine.
Prepare cream cheese mix-in: blend 4 oz cream cheese and 1/4 cup sugar.
Microwave mix for 45 seconds until soft.
Hollow out center of ice cream pint, add cream cheese.
Return pint to machine, press "Mix-In" for thorough blending.
For visible swirls, gently mix by hand.
Twist bowl left to remove from machine, lift lid.
Your red velvet ice cream is ready to enjoy!