Use regular Oreos, not Double Stuf - the extra creme makes the crust greasy. Pack the crusts firmly; for an extra-sturdy crust, use up to 4 tablespoons of butter. An electric mixer is required for the filling -hand-whisking will not bring the cream to stiff peaks. Whisk the ganache rather than stirring it. Have a mini cheesecake pan? It works too and yields about 12-14 taller cheesecakes. STORAGE: these are meant to live in the freezer - the filling has no gelatin and sets from cold, so freezing keeps the cleanest edge. Airtight container up to 2 months; set out 10-15 minutes before serving. Refrigerator works up to 4 days, but the texture turns softer. Ganache freezes well, so top them before storing.