Preheat the oven to 350℉. Place a 12-inch square of parchment paper over an 8-inch square baking dish and press it down onto the bottom and up the sides of the dish.
In a large bowl, stir together the oats, flour, flaxseeds, brown sugar and salt. Stir in the peanut butte and melted butter. Press the oat mixture into the prepared baking dish, reserving 1/2 cup for topping. Spoon 4 lines of jam across the top of the oat mixture. Sprinkle the remaining 1/2 cup of oat mixture over the jam.
Bake for 30 to 35 minutes, or until slightly browned and firm.
Cool completely, at least 1 hour. Cut into squares.
Notes
Suggested substitutes for flaxseed: chia seeds or wheat germ.
To make these gluten-free: Use gluten-free oats. Use an all-purpose gluten free flour (I like to use the Cup4Cup brand for baking). Flaxseed is naturally gluten free. And just be sure to use brands of peanut butter and jam that are known to be gluten-free.