Combine crumbs and butter; press into bottom of lightly-greased 8- or 9-inch springform pan. Chill.
Combine basil, garlic, and mayonnaise in a blender, blend until smooth and set aside. In mixing bowl, beat together the ricotta, blue and Parmesan cheeses until blended. Beat in basil mixture. Spread mixture over crust, pressing and smoothing top. Chill at least 8 hours or overnight. When ready to serve, remove sides of pan and place cake on platter. Press chopped, toasted almonds ontil sides of cheesecake, if desired. To garnish top of cheesecake, make a "flower" with slivered almonds and chive stems, if desired. Serve with assorted crackers, vegetable slices and toast.