Chocolate Morsels Versus Chocolate from a Slab

Recently, I was talking to my buddy Andris (not to name drop, but he's the creator of the Baking Steel--and kind of a big deal) about an important subject: pizza. He was telling me this interesting thing about cheese: it makes a difference if you use the pre-shredded kind on your pizza, versus shredding or cutting your own from a block. Why? Because the pre-shreds are kept from caking together with a little cornstarch in the package. As it turns out, this cornstarch can actually affect the baking: it makes the cheese brown faster, giving a false indication of doneness on your pizza. So, for best results, shred yo' own cheese.

All of this was fascinating, of course, because I consider pizza a highly important part of my life. But since I love sweets, too, I found myself wondering: does this apply to chocolate, as well?

As in: does it make a difference if you bake with chocolate morsels versus chocolate from a slab? I'd like to explore this subject, if you'll go along with me.

Note:

There are a huge variety of both morsels and slab chocolate types, some of which are mentioned below. To figure out what type of chocolate to buy, this guide to buying chocolate will help you out bigtime. But for my more broad overview, just assume that we're pairing up the same type of morsels and slab chocolate side by side.

Chocolate morsels 

What they are

Chocolate morsels (or chocolate chips) are small Hershey's kiss-shaped bits of chocolate which are most famously used as mix-ins for cookies. Far from just chocolate, the morsels are available in white chocolate, various degrees of chocolate from milk to dark, peanut butter, toffee, and even raspberry. 

What to use them for

Mainly, you want to stick to morsels as a mix-in. Those little morsels are not, technically speaking, designed to melt. They're designed to hold their shape in chocolate chip cookies--that was exactly why the product was developed. This effect is heightened by the fact that they are often treated with wax to make them more firm. So while yes, you can melt them, they might be harder to handle once melted or might set up slightly differently than if you used untreated chocolate. 

Another note about morsels is that their treatment may yield a different burn point: they might get over-toasted too quickly if you substitute them for slab chocolate. The cornstarch used to store them may make them burn too quickly.

Slab chocolate

What it is 

A slab of chocolate which can be coarsely chopped and incorporated into baking recipes. Far from just one type of slab chocolate, this category can include everything from white chocolate to milk chocolate to a myriad of different percentages of dark chocolate. It includes unsweetened (sometimes called "baking") chocolate blocks. I would even go so far as to put some chocolate bars in this category, though this might prompt argument.

What to use them for

slab chocolate is typically the stuff you'll use in recipes where you want melted chocolate (fudge frostings, brownies, etc). It will incorporate rather than being treated as a mix-in.

You can substitute chopped slab chocolate for morsels in recipes, but know that it will melt differently, and that little shards of the chocolate will form straciatella-like nubs of chocolate in cookies (not that this is a bad thing, but it is something to keep in mind). 

So, to review:

Chips or morsels, unless untreated with wax and stabilizers, are not going to be your best bet for melting. However, they will hold their shape in cookies, which gives a classic result. 

Slab chocolate, which is chopped and then melted or mixed in to recipes, will yield more melty results in cookies, but will melt more reliably for recipes calling for melted chocolate.