Add oats, protein powder, cashew butter, dried rose petals, milk, honey, salt, and the full chai spice blend to a large bowl.
Stir until everything is combined. The batter should be sticky and hold together when pressed. If crumbly, add milk one teaspoon at a time. If too wet, add a tablespoon more oats.
Chill and cut
Press the mixture firmly and evenly into the prepared pan using the back of a spatula or the flat of your palm (dampened slightly so nothing sticks).
Refrigerate for 10 minutes to firm up.
Lift the parchment out of the pan and cut into 8 equal bars with a sharp knife using one clean press per cut.
Notes
Plant-based protein: use about 50g and increase milk by 2-3 tablespoons. Bars will be slightly denser.
Nut-free: substitute cashew butter with sunflower seed butter or tahini.
Vegan: use plant-based protein powder and replace honey with maple syrup.
Gluten-free: use certified gluten-free rolled oats to avoid cross-contamination.
Spice blend tip: mix a bigger batch and store in a small jar. Great stirred into oatmeal or warm milk.
Storage: refrigerate in an airtight container for up to 7 days. Freeze individually wrapped bars for up to 3 months; defrost overnight in the fridge.