For the peach jam: Preheat oven to 350 degrees. In a large bowl, combine all ingredients. Place in an 8x8 baking dish, and bake for 30 minutes. Once done, stir again to combine, then place in refrigerator to cool.
Season steak liberally with salt and pepper. Heat a cast iron pan on medium-high and pour olive oil in to coat the pan. Cook steak, turning occasionally, until desired doneness (will depend on how you want steak cooked). Let rest for 5 minutes, then thinly slice.
Preheat oven to 350. Line baking sheet with aluminum foil. Place slices of bread on sheet and drizzle with olive oil. Bake for 5-10 minutes or until bread is lightly toasted.
Optional: You can place brie in the oven at this time if you'd like your brie a little hotter and easier to spread. Bake this 5-6 minutes, or until gooey but not runny.
Layer the sandwich. Spread peach jam on one side slice of bread and brie on the other. Add steak, and season with salt and pepper.