In terms of woodturning this is a very conventional bowl.
What makes it special is the layering of wedges of different coloured wood, in this case walnut and ash
Two equal square blanks, of woods in contrasting colours are required. They are sawn into pairs of shallow wedges.
The four pieces can be stacked up and still the top surface will be horizontal.
One pair of wedges is rotated through a right angle (still the top surface is horizontal).
Then the second and third pieces in the stack are interchanged.
The hard part is gluing the four pieces together without them slipping to one side as the glue dries (a long bolt through each corner of the stack helps a lot)
Think of it as a bowl filled with contrasting chunks of delicious dark and white chocolate - scrumptious!