Make the Biscuits:
Preheat the oven to 450°F (230°C). In a large bowl, whisk together the flour, baking powder, sugar, and salt. Make a well in the center and pour in the melted butter and buttermilk. Stir until just combined; the dough should be sticky but not too wet.

Prepare the Baking Dish:
Grease an 8×8-inch baking dish with 2 tablespoons of butter. Transfer the dough into the baking dish, spreading it out evenly. Do not flatten the dough too much; it should be rough and rustic.

Bake the Biscuits:
Bake the biscuits in the preheated oven for about 20-25 minutes, or until the top is golden brown and a toothpick inserted comes out clean. Remove from the oven and let them cool slightly in the pan.

Make the Peach Jalapeño Jam:
While the biscuits are baking, prepare the jam. In a medium saucepan, combine the chopped peaches, jalapeño, sugar, lemon juice, ginger, and salt. Bring the mixture to a simmer over medium heat. Stir frequently and cook for about 15-20 minutes, or until the peaches break down and the jam thickens. If you prefer a thicker jam, you can add pectin according to the package instructions.

Finish the Jam:
Once the jam reaches your desired thickness, remove it from the heat and let it cool for a few minutes. The jam will thicken further as it cools. Taste and adjust the sweetness or spiciness by adding more sugar or jalapeño, depending on your preference.

Serve:
Once the biscuits are done, remove them from the pan and break them into pieces. Serve the warm Butter Swim Biscuits with a generous spoonful of the Peach Jalapeño Jam on top.