Preheat oven to 350°F (177°C). Grease a 9-inch pan (round or square) or 9-inch springform pan. Whisk the flour, granulated sugar, cocoa powder, baking soda, and salt together in a large bowl. Set aside. Whisk the oil, eggs, and vanilla together in a medium bowl. Pour the wet ingredients into the dry ingredients, add the hot water, and whisk everything together until combined. Make sure there are no pockets of dry ingredients hiding. Pour the batter evenly into the prepared pan. Bake for 25–27 minutes or until a toothpick inserted in the center comes out clean. Allow the cake to cool completely in the pan set on a wire rack. With a handheld or stand mixer fitted with a paddle attachment, beat the butter on medium speed until creamy, about 2 minutes. This isn’t a lot of butter and it will get stuck on the sides of the bowl, so you may need to scrape down the sides of the bowl with a rubber spatula to really help get it creamed. Add confectioners’ sugar, cocoa powder, 2 teaspoons of heavy cream/milk, and vanilla extract, and beat on low speed until incorporated. Increase to high speed and beat for 3 minutes until it really comes together. Add another teaspoon of milk/cream if it looks a little too thick. Crumble the cooled cake into the bowl on top of the frosting. Make sure there are no large lumps. Turn the mixer on low speed and beat the frosting and cake crumbles together until combined. Measure 1 scant Tablespoon (20g) of moist cake mixture and roll into a ball. Place cake balls on a lined baking sheet. Refrigerate for 2 hours or freeze for 1 hour. Melt the coating in a 2-cup liquid measuring cup (best for dunking!). Microwave in 20-second increments, stirring after every 20 seconds until completely melted and smooth. (Or you can use a double boiler and pour a little at a time into the liquid measuring cup.) Let the coating cool down for a few minutes before you begin dipping. If it’s too hot when you dip, the coating will crack. Remove only 2–3 cake balls from the refrigerator at a time. (Keep the rest cold!) Dip one end of a lollipop stick about 1/2 inch into the coating, then insert into the center of the cake ball. Push it about halfway to 3/4 of the way through the cake ball. Dip the cake ball into the coating until it is completely covered. Make sure the coating covers the base of the cake ball where it meets the lollipop stick. Very gently tap the stick against the edge of the measuring cup to allow excess coating to drip off. Decorate the top with sprinkles and place upright into a styrofoam block or box (as explained in the blog post above). Repeat with remaining cake balls, only working with a few out of the refrigerator at a time. The cake balls must be very cold when dipping! Coating will set within an hour. Store cake pops in the refrigerator for up to 1 week.