Dry tenderloin: Cooked past 145°F. Always use a thermometer. Pale exterior: Sear not long enough or pan not hot enough. 90 sec per rotation minimum. Thin sauce: Simmer 2 extra minutes before cream. Ensure 36%+ cream and block Parmesan off the heat. Slow cooker: Sear first. Build sauce. Transfer for 3 to 4 hours. Add Parmesan and basil after opening the lid.