Heat your oven to 400ºF. While the oven heats up, take the eggs and milk out of the refrigerator to bring them closer to room temperature.
In a large mixing bowl, whisk together the eggs and cashew milk until smooth. Whisk in the lime zest, sugar, and salt. Slowly mix in the flout to for a thin, smooth batter.
Add the butter into a 9-inch oven-proof skillet (preferably cast iron). Place in the oven for 2-3 minutes, or until the butter is melted. Swirl te pan to coat it with melted butter; pour in the batter.
Bake for 20 minutes, or until the Dutch baby is puffed and golden brown. Remove from the oven.
If desired, dust with powdered sugar. Top with fresh mango slices. Serve immediately.