Make sure the bread cubes are stale. If fresh bread is used, the bread will not be able to absorb the custard mixture.
In a large mixing bowl, whisk together the eggs, heavy cream, sugar, maple syrup, vanilla and salt. Continue whisking until fully combined. Fold in the stale bread cubes. Gently fold the mixture together until fully incorporated. Cover the bowl with plastic wrap and place in the refrigerator overnight.
The next day, spray or grease a large casserole dish. Pour the bread pudding mixture into the casserole dish and smooth out the top. Place the casserole dish in the convection steam oven on rack position 2. Turn the oven on by selecting the Convection Humid Mode set to 175°C. Check the bread pudding after 45 minutes. Continue baking until it is fully set and deep golden brown on top.