In a saucepan combine butter, diced apples, chopped pecans, brown sugar, and cinnamon. Cook for 4-5 minutes over medium low heat, and then add in corn starch. This will allow the sauce to thicken. Place your brie cheese in an oven safe dish and score the top with a knife. Top with your apple and pecan mixture and bake at 350°F for 10-15 minutes. Serve with toasted baguette slices and follow for more easy recipes!