Preheat your oven to 400 degrees f.

Pat the tenderloin completely dry with a paper towel and place it in a baking dish. Let it get to room temp by setting it on the counter for about 30 minutes prior to cooking.

In a small bowl, whisk together the mustard, honey, oil, apple cider vinegar, pressed garlic, sea salt, and pepper until well combined.

Rub the tenderloin all over with your honey mustard mixture. Keep and set aside about 1/4 of this mixture (untouched by the raw meat) to baste at the end of cooking.

Roast in your preheated oven for around 40-45 minutes, or just until the internal center temperature reaches 145 degrees f. This will result in a roast that is both safe and at its best quality—juicy and tender.

Baste with the sauce from the bottom of the dish every 15 minutes during roasting.

Once your tenderloin is finished cooking, baste with the remaining mustard mixture that you sat aside (untouched by raw meat) and remove from the oven to rest for 5 minutes.

Slice, garnish with parsley and enjoy immediately!