Look for mustard greens and collards at your local grocery store or farmer's market. Both of these are staple southern greens, and high in minerals, vitamins, antioxidants, and other fancy phytonutrients.
Add the onions, garlic, and celery and sauté until onions begin to get translucent.
Add the sliced mushrooms, and stir well. Cook until they soften, about 8 minutes.
Add the water or veggie stock, pepper, and dried thyme and bring to a simmer. Cook for 10 minutes.
Add the paprika and porcini powder, and stock paste/bouillon, then stir in the greens. You'll have to push them down into the pot to fit them all in. As they cook they'll reduce in size.
Cook for another 10 minutes. Season with salt and pepper and hot sauce to taste then serve.