Prep. Preheat your oven to 350°F (175°C) with the rack in the center. Prepare a 12-cup Bundt pan by greasing it with shortening and dusting with flour or using a non-stick cooking spray with flour added.
Make the batter. In a large mixing bowl, cream the butter and sugar on medium-high speed for 3-5 minutes until light and fluffy. Then, add the eggs, one at a time, mixing on medium speed after each addition. Add the almond or vanilla extract.
Combine the dry ingredients. Whisk together the dry ingredients in a separate bowl: flour, salt, and baking powder. Add the dry ingredients to the butter mixture in three parts, alternating with the milk. Begin and end with the dry ingredients, mixing on low speed. Finally, stir in the diced peaches by hand.
Bake. Transfer the batter to the prepared Bundt pan, spreading it evenly. Bake for 45-55 minutes until a toothpick inserted into the cake comes out clean or with a few moist crumbs. Let it cool in the pan for 15 minutes, then carefully turn it out onto a cooling rack. Let it cool completely for about 1 hour before frosting.
Prepare the icing. In a small bowl with a whisk, mix the powdered sugar, hot water, vegetable oil, and a splash of peach juice. The icing should be thick and not pourable.
Frost the cake. Transfer the icing into a piping bag (or a plastic bag with a corner cut off) and drizzle it over the cake. It will slowly drip down the sides and smooth out.