Semolina, coarsely-ground durum wheat, is often used to make pasta. It is available at health food stores and Italian markets. One great brand to try is Bob's Red Mill, which is available in many supermarkets.
A simple raspberry coulis would be a terrific sauce for this cake. In a food processor or blender, puree 1 cup of raspberries (thawed frozen or fresh) with a tablespoon of sugar and a tablespoon of lemon juice or water. Strain and serve.