In a large skillet, toast the pecans over medium heat until fragrant and lightly browned, about 8 minutes. Remove from the pan and set aside.
Meanwhile, remove any wilted outer leaves from the brussels sprouts and cut off the stems. Soak the sprouts in cold water and drain well.
Using the same skillet, melt the butter over medium heat until bubbly. Add the brussels sprouts and seasoned salt. Stir and cook, tossing frequently, until barely tender, 12 to 15 minutes.
Add the brown sugar, pepper and reserved pecans to the skillet. Toss the brussels sprouts to coat and cook, stirring frequently, until the sugar is melted and the brussels sprouts are coated in the melted sugar and pecans, about 2 more minutes. Transfer to a warm serving dish and serve immediately.