In a Dutch oven, melt the butter in the oil over medium-high heat.
Brown the pork cubes for about 5 minutes, a little at a time to avoid boiling the meat. Season with salt and pepper to taste.
Add the thyme, oregano, salted herbs, and garlic. Brown for 1 to 2 minutes, then sprinkle with flour.
Stir everything and cook for 2 minutes, avoiding browning the flour.
Deglaze with the white wine, reduce for 3 minutes, and moisten with the chicken broth.
Add the carrots, leeks, onion, and bay leaves.
Cover and simmer for 1 hour over medium heat.
Remove the pork cubes from the broth and set them aside to keep warm.
Strain the cooking juice into a sieve and set the vegetables aside in a bowl.
Pour the juice into a saucepan and reduce for a few minutes over medium-high heat.
Meanwhile, beat the cream and egg yolks vigorously in a bowl.
Pour into the broth, stirring constantly, and reduce until thickened.
Coat the pork with this sauce. Garnish with the vegetables used to make the broth and chopped parsley.