Mix the wet ingredients. In a medium bowl, whisk together the vanilla yogurt, milk, and vanilla extract until smooth.
Add the dry ingredients. Stir in the rolled oats, brown sugar, cinnamon, and salt.
Mix until everything is combined.
Layer the peaches. Divide half of the oat mixture evenly among four jars or containers. Add a layer of diced peaches on top. Then spoon the remaining oat mixture over the peaches.
Top with remaining peaches. Place the rest of the peaches on top of the oats.
Gently press them down so they are partially submerged.
Refrigerate overnight. Put the lids on your jars and refrigerate for at least 6 hours, or overnight. The oats will soften and absorb the liquid.
Serve cold or warmed. In the morning, give the oats a stir. You can eat them cold straight from the fridge, or microwave them for 30-60 seconds for a warm breakfast.
Add optional toppings like pecans or granola before serving.