For Chocolate Ganache

1. Place the chopped chocolate or chocolate chips and salt in a heat-proof bowl.
2. Bring heavy cream just to a boil in a small sauce pot.
3. Pour the hot cream over the chopped chocolate.
4. Wait five minutes for the hot cream to melt the chocolate, then whisk the mixture until the ganache is silky and shiny.
5. Cool the ganache to at least room temperature before filling your baked shells. You can cool it faster by placing it in the refrigerator and whisking it every five or ten minutes.
6. Store leftover chocolate ganache in the refrigerator. 

For Chocolate Macaron Shells

1. Bring the egg whites to room temperature (no need to "age" them for days, it's a myth). Preheat your oven to 300° F with an oven thermometer inside to gauge its accuracy.
2. Measure or weigh out all your ingredients. Line two baking pans with parchment paper (or silicone baking mats) with printable macaron templates underneath.
3. Sift together the confectioner's sugar, almond meal (flour), cocoa powder, and salt.
4. Place the egg whites in the bowl of a stand mixer with a whisk attachment. Or a large mixing bowl if you're using a hand mixer.
5. Whip the egg whites on medium speed until they're foamy. While continuing to beat, slowly rain down and beat in the granulated sugar. If using cream of tartar, add it once the meringue first becomes opaque, and reaches soft peaks.
6. Turn the mixer up to medium-high speed and beat until the meringue is voluminous, opaque, and shiny. The little peaks of meringue that form off the edge of the beater will stick nearly straight up. The French use the term bird's beak to describe a firm peak, which is the classical French meringue consistency used for macarons.
7. Fold in the dry ingredients in a few additions. Mix a bit firm at first to encourage cohesion. Then use classic folding strokes; scraping around the sides of the bowl, then up from underneath the mixture, and over through the top. Aim for a batter that ribbons off the spatula in a somewhat thin stream, and settles back into itself within about ten seconds. Take care not to overmix. 
8. Transfer the batter to a piping bag fitted with a small round tip. I set my piping bags tip-side down inside a large glass for hands-free transfer. Lay the bag flat on the counter, and push the batter down towards the tip. Twist the top of the bag tightly at the point where the batter stops, and hold it tip-side up until you are ready to pipe.
9. Following the template you chose, pipe rounds of batter onto the lined pan. Hold the piping bag vertical, and about a quarter-inch above the pan. Squeeze the piping bag from the top until the batter reaches the inner edges of the black circle. Immediately stop squeezing and flick the tip away in a tiny, circular motion.
10. To help the tops of piped batter settle, lightly tap the pan on the counter. Or with one hand, tap the underside of the pan a few times. Be careful not to tap too hard, this will cause air bubbles to pop. And leave you with potholed macs.
11. If you like and for a bit of insurance, let the piped macaron batter rest on the counter for 10 to 20 minutes. 
12. Bake at 300° F for 14 to 17 minutes, depending on the size of your shells. Rotate the pans once halfway through baking. Macarons are done when the tops don't wiggle away from the bottoms when very lightly pushed. But before the bottoms begin to brown.
13. Cool a few moments before sliding the parchment paper or mat off the baking pan. Gently remove the shells from the mat or parchment by pushing up from underneath the liner to release the bottoms.
14. Fill with your filling of choice. The easiest way to fill the baked shells is to transfer your filling(s) to a piping bag or plastic baggie. There's no need for a tip unless you want a more decorative pattern. Simply snip a very small opening in the corner of the bag.
15. Pipe a small round of filling on half of the macaron shells, leaving a bit of space between where the filling ends and the edge of the shell. Top each filled shell with another. 
16. Store the filled macarons chilled for 24 hours before serving. If you can wait that long!

Easy Peanut Butter Buttercream

1. Place all of the ingredients in a medium mixing bowl or the bowl of a stand mixer fitted with a paddle attachment.
2. Beat at medium speed until smooth, scraping the sides and bottom of the bowl with a flexible spatula as you go.  
3. Store leftover buttercream in the refrigerator, but bring it to room temperature before using it. It can help to briefly beat the buttercream after chilling to revive it.