Preheat oven to 350. Grease 4 muffin tins, if you have that many. Otherwise, you may have to wipe them out and re-grease them between batches.
In a large bowl, cream the butter and sugars together.
Mix in the vanilla
Break and beat in the eggs, one at a time.
In a small cup, combine the baking soda and sea salt. Measure out the two teaspoons of hot water, pour them into the cup and mix to dissolve. Fold this mixture into the batter.
Add in the flour, a cup and a half at a time.
Measuring Hint: Pack the flour down as you measure, to give the cookies the right consistency. They need to be a little heavier on the flour to make the cups. I like to use a small gravy ladle to help measure and pack.
Add in the mini semi-sweet chocolate chips.
Use a large cookie scoop to measure out the cups (if you don’t have one, the measurement is about 2 tbsp). There is no need to press the dough into the cup, it will spread while baking.
Bake for 9-10 minutes.
Upon removing them from the oven, you need to make the cups immediately before they cool. Take a nicely rounded spoon, and press down the center of each cookie. If some of the cookie sticks to the spoon, wipe it off before pressing the next cookie or it will only stick more. Do not overbake, or the center won’t depress enough.
While the cookie cups are cooling, make the peanut butter centers.
In a medium bowl, combine the peanut butter, butter and vanilla and mix together.
Mix the sifted powdered sugar in, about a cup at a time, until you must start mixing with your hands. You can turn it out onto a surface covered with powdered sugar if it’s easier.
Make the peanut butter mixture into patties that are about 1 ½” in diameter and about ¼ thick, similar to the size of a peanut butter cup. Lay them on parchment or wax paper on a cookie sheet until you have enough to fill the cups. You will probably end up with more than 48 discs. I keep the extra in the freezer.
Once the cookie cups are cool, lay a peanut butter disc in each cup.
Melt the chocolate chips in a double boiler, or in the microwave, and then mix in the shortening.
Spoon a small amount of chocolate on the top of the peanut butter and use a knife to smooth it to the edge.
The chocolate will harden at room temperature, or you can speed up the process by putting them in the fridge for a couple minutes.