Heat your oven to the “keep warm” setting (170°F).
Season both sides of the sole fillets with kosher salt, black pepper, and garlic powder.
Sprinkle 2 tablespoons of almond flour on each fillet, 1 tablespoon per side, and gently spread it with your hand to coat the fish.
Heat the clarified butter in a large 12-inch nonstick skillet over medium-high heat. Swirl or brush to coat. Place the sole fillets in the skillet and cook them until just done, about 2 minutes per side. Lower the heat to medium if the pan overheats. Transfer the cooked fish to oven-safe plates and keep them in the warm oven.
Carefully wipe the skillet clean with paper towels. Add the butter. Heat the butter over medium-high heat, swirling to melt. Cook until the butter starts to brown, about 1 minute, then immediately remove the skillet from the heat and stir in the lemon juice.
Remove the plates from the oven. Pour the butter-lemon sauce on the fish fillets and sprinkle them with parsley. Serve immediately.
Video
Notes
The most important thing is to avoid overcooking the fish, or it will turn out dry. Two minutes per side over medium-high heat is perfect. If I lower the heat to medium, I cook the fish for 3 minutes on the second side.
Almond flour doesn't adhere to the fish as well as all-purpose flour. It's still delicious- and to me, it's worth it. But you should be aware of this issue.
Sole is a delicate fish that easily falls apart, especially if it has been frozen and thawed. Be sure to flip it carefully, and if it falls apart, don't despair - it will still taste exquisite.
Make sure you use a nonstick skillet to minimize the risk of sticking. This is especially true when using almond flour, which tends to stick more than wheat flour.
The leftovers keep okay in the fridge, in a sealed container, for up to three days. But they are not as good as when freshly made. Reheat them gently, covered, in the microwave at 50% power. I don't recommend freezing the leftovers.