Preheat oven to 350 degrees. Place foil or paper liners in a muffin pan and mist with cooking spray (foil liners work better). Remember, we always bake one pan at a time, so have the second muffin pan ready with the remaining liners and have them sprayed.
1.In a large mixing bowl, combine the cake mix with seltzer and mix at low speed for about 30 seconds. Add remaining cupcake ingredients. Mix at medium speed for another minute or two.
2.With a rubber spatula, make sure all the dry ingredients are mixed from the bottom. Let batter sit for about 5 to 7 minutes.
3.After the short wait, mix gently just once. Fill your muffin cups with the batter. You should have enough for 16 cupcakes.
4.Bake the first batch for about 15 to 18 minutes. Turn pan around after about 8 minutes. Check to see if they are done by using a wooden skewer or toothpick. It should come out clean with dry to moist crumbs.
5.Place the pan on a cooling rack and let the cupcakes cool completely. Put the next pan in the oven and repeat the same as the first pan.
6.When the both pans are cooled. Start your frosting. In a small to medium nonstick saucepan, pour out the condensed milk (use a rubber spatula to get all the milk out) and add the water and cocoa powder. Cook over low heat until the mixture comes to a slight boil. Continue to stir (you don’t want burnt frosting). Let it boil just a little bit, and then remove from heat. Keep stirring. Add the vanilla extract. You should have a nice smooth consistency. If the frosting is too thick you can add a little more water and mix up again.
7.Let frosting cool down just a bit.
8.Place your cooled cupcakes on a serving plate and frost each one. You will have more than enough frosting for each cupcake.
9.Now sprinkle a few pieces of the peanuts on top of each cupcake while the frosting is still wet. Enjoy!!