volcano-shaped birthday cake

They used to advertise a "volcano" cake that "erupted" frosting "with the push of a button".  Well, my kids have a thing for volcanoes, so I've made 3 volcano cakes within the year.  I, of course, never bought the "erupting" kind - mine are just chocolatey-peanut-buttery-goodness.

To make one, put a shot glass upside-down in a glass bowl, and spray the whole thing with baking spray.  Pour in a chocolate cake mix and bake as directed:

Mine rose a little too much this time and so it looks like it's floating here:  When it's baked, flip it over onto a cookie sheet (or a cooling rack covered with waxed paper, or whatever you're going to serve it on.  Remember, you won't be moving the cake again) and remove the shot glass.

Make peanut butter frosting (1/2 cup peanut butter, 1/2 tsp vanilla, 1 cup powdered sugar, and milk or water until it's the right consistency) and add red food coloring.  Mine is never "dark" enough so I added some cocoa powder to darken the look of the "lava".  Heat it in the microwave, just 30 seconds or so, until it's "pourable", and pour it over the cake.  I always pour unevenly, so you can see some of the cake through the "lava".  When you're done, you have a "volcano" cake.