Add the oats to a 10 to 12 ounce jar. Pour in the milk and stir until all the oats are submerged.
For a creamier jar, add the yogurt, chia, honey, and vanilla. Stir very well, rest 5 to 10 minutes, then stir again. If it’s thick, add a splash of milk.
Cover and refrigerate at least 2 hours or overnight. Stir before serving. Add toppings just before eating. Store up to 5 days; if it thickens, loosen with milk.