Take the wine and sugar mixture and put it in a small saucepot. Bring to a boil, reduce heat, and simmer for 10–15 minutes, until reduced in volume by about three-quarters, leaving you with a thick wine reduction.
Set aside, keeping warm.
Lay the skirt steaks onto a flat work surface and pat dry with paper towels.
Pound meat on both sides with a meat tenderizer.
To make the marinade, combine the remaining cup of red wine with the brown sugar, whole grain mustard, garlic and oregano.
Drizzle in a little bit of walnut oil and season with black pepper. Pour over the steaks and marinate for 20–30 minutes.
Remove the steak from marinade, discarding leftover marinade.
Preheat grill to 550–650°F.
Place goat cheese and crème fraîche in a bowl and whisk together. The consistency should be similar to sour cream. Season with salt and white pepper.
Season the steak liberally on both sides with kosher salt and black pepper, rubbing the seasoning into the meat. Grill skirt steaks for 1–3 minutes per side for rare to medium-rare doneness, basting with the reserved red wine reduction. Remove from grill.
Allow the steak to rest for 5 minutes. Cut each skirt steak into thin slices and spoon some goat cheese crema over the top. Drizzle with extra walnut oil and red wine reduction and sprinkle with walnuts.