Trim any fat off the pork tenderloin, then fold over any tapered ends to achieve approximately even thickness thrroughout. Preheat your oven to 300° Fahrenheit (150° Celsius).
650 grams pork tenderloin
Make the herb sauce by combining all herb ingredients and blend in a food processor until combined (don't salt too much because the bacon will add salt as well). Rub all over the pork, then lay out the bacon, letting it slightly overlap, until you have the length of your tenderloin.
1 handful fresh parsley, 1 rosemary twig, 1 handful fresh chives, 2 garlic cloves, 1 Tablespoon olive oil, salt and pepper, 100 grams bacon
Get kitchen twine, short skewers or toothpicks ready. Roll the pork tenderloin in the bacon and secure with your tools. If using toothpicks, make sure you count how many you're using, so you know to remove them all! Believe me, it's easier said than done!
Heat ½ tablespoon of each butter and avocado oil over medium high. This is to bring down the smoke point of the butter, yet keeping the flavors. You can also just use avocado oil.
½ tablespoon butter, ½ tablespoon avocado oil
Add the pork tenderloin and brown from all sides. Place onto an oven-safe, rimmed baking sheet prepped with aluminum foil and bake until the internal temperature has reached 140° F or 60° C (it will continue cooking for a bit while you let it rest - recommended internal temperature is 145° F or 62.8° C).
In the meantime, bring a pot of salted water to a boil and whisk together spätzle ingredients (other than butter) and set aside (you could also use store-bought spätzle - my Oma has definitely done it, too).
2 eggs, 200 grams flour, ½ teaspoon salt, 150 milliliters milk, ⅛ teaspoon ground nutmeg
Sauté the mushrooms in the cooking liquids from the pork (I recommend either using a large pan or cooking them in batches). Grate or mince the garlic and add when the mushrooms are just about done for 1 minute. Add the wine and broth and allow to simmer down for 2 minutes. Add remaining ingredients and season with salt and pepper. Keep warm.
750 grams mushrooms, 100 grams bacon, 1 medium-sized onion, 3 cloves garlic, 1 tablespoon tomato paste, 200 milliliters heavy whipping cream, 100 milliliters sour cream, 100 milliliters broth, 100 milliliters white wine, Worcestershire sauce, salt and pepper
Cook spätzle by pressing the batter into the salted, boiling water. Stir and allow to boil for 2 minutes before straining (if working in batches, a large skimmer comes in handy). Place in a serving bowl while fresh out of the water and toss with the butter to allow it to melt. Garnish with a bit of chopped, fresh parsley.
1 Tablespoon butter
Arrange the sauce on a platter, slice the tenderloin and place it over the mushroom sauce. Garnish with some fresh, chopped parsley.