In a blender, purée milk, oats, yogurt, peanut butter, honey, chia seeds, vanilla, and salt until smooth.
Divide oat mixture between 2 (8-oz.) jars or containers. Cover and refrigerate until oats are thickened, at least 4 hours.
In a small heatproof bowl, microwave chips in 30-second increments, stirring between each, until melted and smooth, about 1 minute total. Spoon chocolate over oats and refrigerate until chocolate is firm, about 10 minutes.
Top oats with bananas, peanuts, cocoa nibs, and honey (if using).
Make Ahead: Oats (without toppings) can be made 5 days ahead. Keep refrigerated.
