Combine oats, water, and milk in a bowl and soak in the refrigerator overnight or for 1 hour in the morning. If you prefer not to soak, that's okay too.

Transfer the mixture to a small pot and add zucchini, lemon juice, and lemon zest (if desired).

Bring to a boil over medium heat, then reduce to low and simmer for about 5 minutes, stirring continuously to prevent sticking.

Once well mixed, transfer to a bowl and top with raspberries and cashew butter. Add coconut flakes if desired.