Coat the 4-quart insert of your slow cooker with nonstick cooking spray.

In a large mixing bowl, whisk together the oil, applesauce, brown sugar, cake spice, salt and eggs until thoroughly mixed. Add the mashed banana until incorporated. Stir in the milk.

In a medium mixing bowl, stir together the oats and baking powder.

Stir the dry oat mixture into the wet mixture until combined.

Add the peanut butter and continue stirring until combined.

Stir in the raisins.

Pour mixture into prepared slow cooker.

Use 3 or 4 sheets of paper towel between slow cooker insert and lid to absorb extra condensation and prevent it from falling back onto the oatmeal.

Cover with slow cooker lid and cook on LOW for 3 to 5 hours, or until the edges are golden and the center is set.

Serve warm or let it stand in the slow cooker for up to an hour before cutting into pieces for serving.