2 large bunches collard greens (about 1 1/2 lb.), center stems removed and leaves cut into ½-inch strips
2 tsp vegetable oil
6 oz thick-cut smoked bacon
Unsalted butter (if needed)
2 large shallots, finely chopped
3 tbsp all-purpose flour
1½ tsp sweet paprika
2 c whole milk
2 c heavy cream
Freshly ground black pepper
Blanch greens in a large pot of boiling salted water until bright green and beginning to soften, 3–4 minutes. Transfer to a large bowl of ice water to cool. Squeeze dry.
Heat oil in a large heavy pot over medium heat. Add bacon and cook until fat is rendered and bacon is crisp, 5–7 minutes. Using a slotted spoon, transfer bacon to paper towels to drain; set aside.
Drain all but 3 tablespoons of bacon drippings from pot, adding butter if needed to measure 3 tablespoons. Add shallots; cook over medium heat, stirring occasionally, until soft, about 5 minutes. Add flour and paprika; stir constantly for 2 minutes. Whisk in milk and cream; bring to a boil, whisking often. Stir in greens; reduce heat to low. Simmer, stirring often, until greens are tender and sauce thickens, about 30 minutes. Season to taste with salt and pepper.
Transfer creamed greens to a serving dish; garnish with crumbled bacon.