Pat fish dry and season with salt and pepper. Spread flour on a piece of wax paper. Place each fillet or whole fish in the flour and coat both sides well. Dust off any excess. Add the sesame seeds to the remaining flour and mix well.
Set out a large plate or platter.
In a large shallow container, beat the eggs with the sesame oil. Dip each fish or fillet in the egg mixture, then in the flour-sesame mix, coating it well, and place it on the platter. When all the fish are coated, place the platter in the refrigerator for about 10 minutes.
Preheat the oven to 200°. Place a wire rack on a baking sheet and set it in the oven. Place 4 ovenproof plates in the oven to warm.
Pour the peanut oil into a large heavy skillet or saute pan to a depth of 1/2 inch. Heat the oil over medium-high heat until it is very hot but not smoking (375°). Just as the surface begins to ripple, take the fish out of the refrigerator and place as many in the pan as will fit without crowding, flesh-side down.
Fry the fish 3 minutes on each side or until golden. Transfer the cooked pieces onto the wire rack to stay warm while you finish cooking the rest. Divide the fish among the warmed plates, and splash them with hot sauce. Garnish with fresh cilantro sprigs, if desired. Serve immediately.