Keep the skillet on the stovetop and the heat to simmer (low-medium). Add the chicken stock, capers and 1 tablespoon of lemon juice. Bring to a simmer and stir throughout, scraping the fish renderings left behind in the pan into the sauce for more flavor. At this time, you may add some white wine (about 2-3 tablespoons). Cook for about 3-5 minutes until the sauce has reduced by a 1/3. Remove from heat, add 1 tablespoon of butter, stir until incorporated. Pour over the fish.