In a skillet, melt 1 tablespoon of olive oil and 1 tablespoon of butter over medium heat. Add 1 minced shallot and 2 cloves of crushed garlic. Cook for about 3 minutes until fragrant and translucent.

Add 8 ounces of chopped cremini mushrooms to the skillet. Sauté for 5-7 minutes until browned and moisture has evaporated.

Pour in ½ cup of chicken or vegetable broth to deglaze, then stir in 4 cups of fresh spinach. Cook until wilted, about 2-3 minutes.

In a bowl, mix the cooled mixture with 1 cup of panko breadcrumbs, ½ cup of grated Parmesan cheese, fresh herbs, and 1 egg yolk. Season with salt and pepper.

Trim any silver skin from the pork tenderloin and butterfly it. Optionally pound to an even thickness.

Brush the inside with olive oil and Dijon mustard, season with salt and pepper, and spread the stuffing evenly before rolling tightly.

Using butcher's twine, secure the rolled tenderloin at intervals of about 2 inches and season the outside with more salt and pepper.

In a skillet, heat another tablespoon of olive oil. Sear the tenderloin for about 3-4 minutes on each side until golden brown.

Preheat the oven to 375°F (190°C). Transfer the seared tenderloin to a roasting pan and roast for approximately 25-30 minutes, until internal temperature reaches 145-150°F.

Remove from the oven and let rest for at least 10-15 minutes before slicing. Remove the twine before serving.

Slice the tenderloin and serve with holiday sides, garnishing with fresh herbs.