DIGITAL SCALE: I can't stress enough how important it is to measure out your ingredients by weight and not volume. Digital scales are fairly inexpensive. I bought mine at Walmart for less than $20. AND it's also great for weighing packages I need to ship. Buying a scale and measuring by weight will save you money in the long run from wasted almond flour and bad batches of macarons.
I truly believe 99% of the myths and overly complicated "troubleshooting" tips I've heard comes from starting with ingredients that have not been properly measured out.
SILICON MIXING SPATULA/SPOON
PIPING BAG: These can be either disposable or a reusable silicon version like ones sold by Fat Daddio. We suggest a 16-18 inch bag. Anything smaller and you'll have to fill you bag with batter twice.
Warning: Do not use a zip-top bag or else the Macaron god's will come and find you. As we'll discuss later, HOW you pipe your macarons in perhaps the #1 downfall in making these delicate cookies. We've seen one too many zip-top bags explode, rip, fail etc to ever suggest this is a great alternative.
ROUND PIPING TIP: Alteco #805, Wilton #12. Any round tip with about a 1/2 inch opening.
STAND MIXER FITTED WITH A WHIP OR HAND HELD MIXER FITTED WITH WHIP: Make sure the bowl and whip attachment are clean and free of greasy residue.
2 BAKING SHEETS: Our full recipe will fill up two baking sheets. Use the flattest, least dented sheets you have. And make sure they're sturdy enough so it won't warp or "pop" during baking.
PARCHMENT PAPER: We recommend buying flat and/or pre-cut sheets of parchment paper instead of the one roll which never seems to want to flatten out. You can usually find this in the baking section of the grocery store or at stores like Sur La Table.
2 SILPATS: Silpats are a pastry chef's best friend. They're reusable, promote even baking and nothing can stick to them. If you don't have a Silpat or aren't ready to commit to buying one just yet, you can use just parchment paper.
1.5 INCH BISCUIT/COOKIE CUTTER OR ANYTHING YOU CAN TRACE A 1.5 INCH CIRCLE: Use this to make the macaron stencils we'll talk about later.