We took our mother out for her 90th to a fine dining Italian joint. I had an appetizer simply described as "Grilled Stuffed Shrimp on Crostini with Special Seafood Sauce." The primary flavor of the sauce was obviously tomato, with great umami, but due to the lively conversation I did not concentrate adequately on the flavors. It was very thick, richness of cream, possibly some sweet red pepper puree, possibly a bit of saffron, salt. Smooth, no bits or pieces of anything. So how would some chefs here suggest making such a sauce? Mainly getting the thickness (rue/thickener and/or reduction?), type of cream to use and great tomato umami.