Prep Ahead: Line 9 cups of a muffin pan. Soak dates in hot water for 10 minutes (you can skip this step if your dates are extra soft).
Toast oats (optional): Add oats to a pan and place over medium heat. Toast until golden and nutty, stirring frequently to prevent burning.
Make nougat: Add oats to a food processor and grind oats into small pieces. Drain dates and add to food processor. Blend until dates are distributed well with the oats. Add milk and pulse a few times until the mixture clumps together.
Press the nougat mixture into the lined muffin cups.
Make mousse: Drain dates and add to the food processor along with silken tofu and peanut butter. Blend until well combined - there may be small date chunks but the tofu and peanut butter should be smoothly combined.
Divide mousse into the muffin cups on top of the nougat. Place into the freezer for 1 hour.
Melt chocolate: Add chocolate chips and coconut oil to a microwave-safe bowl. Microwave in 30 second intervals, stirring between each interval, until chocolate is melted.
Add chocolate to mousse cups: Take the mousse cups out of the freezer and add a small spoonful of melted chocolate on top of the mousse. Place back in the freezer until mousse is fully frozen.
Store snickers mousse cups in the freezer for up to a month. They should be soft enough to eat straight from the freezer, no thawing necessary.