Pour the cashew milk into a small saucepan and warm over low to medium heat until steaming. Do not bring to a boil.
Sift the pandan powder and cinnamon through a fine-mesh strainer directly into the warm cashew milk. Whisk immediately to incorporate the powders, then whisk in the maple syrup and vanilla. Continue heating gently until warmed through.
Remove from the heat. If desired, froth for about 30 seconds with a handheld milk frother. Pour into a mug and garnish with edible rose petals.
Notes
Prevent clumps: Sift the pandan powder and cinnamon through a fine-mesh strainer and whisk them into the warm milk right away for a smoother latte.
Watch the heat: Keep the milk over low to medium heat and don't let it boil; it can foam up quickly when it gets too hot.
Adjust the sweetness: Use more or less maple syrup according to your preference.
Plant-based milk: Cashew milk gives this latte a creamy texture and mild flavor. Other unsweetened plant-based milks can be used; try barista-style oat milk if you'd like an especially frothy latte.
Frothing: A handheld milk frother is optional, but about 30 seconds of frothing gives the latte a light, creamy foam.
Rose petals: Use edible, food-grade dried rose petals if adding the optional garnish.