We generally associate the Maillard reaction with extra-high temperatures: smoking-hot pans or grills to brown our steaks, or hot ovens to give us dark bread crusts. But the reaction can actually take place at much lower temperatures; it just happens to occur at a slightly slower pace.
I take advantage of this fact when making a big batch of my Slow-Cooked Tomato Sauce, which spends about six hours in a 300°F oven. Even though the sauce never comes close to the temperatures you'd need for browning steak or bread, it still darkens significantly in color over its long cooking time. This deepening of color corresponds to an equal deepening of flavor. It isn't a bright, fresh tomato sauce. It's a rich, complex sauce that tastes like it cooked all day precisely because it did.
But what if I don't have all day to cook my tomato sauce? What if it's six o'clock on a Wednesday night and I want to be in my pajamas and in bed, with a full belly and a content smile on my face, by eight?
Well, I could turn to Daniel's 40-Minute Red Sauce. It's a great recipe that delivers some of the depth of a slow-cooked sauce by using tomato paste in the flavor base. But, given that I wisely foresaw this exact circumstance and got myself a pressure cooker to deal with it, I've got a better option on the counter.
Because a pressure cooker cooks hotter than a simmering pot—250°F at high pressure, as opposed to 212°F for standard boiling—all kinds of interesting things take place inside its hermetically sealed walls. One of those is browning. We don't typically associate browning with moist cooking methods, like simmering, boiling, or steaming, but a pressure cooker allows liquids to get hot enough to actually start undergoing the Maillard reaction.
In just 45 minutes of cooking at high pressure, you can develop many of the deep flavors you associate with all-day tomato sauces. Good news for a weeknight cook.
You may be saying to yourself, Wait a minute—the sauce in the oven cooked at 300°F for six hours, and you're only cooking at 250°F for 45 minutes. Lower temperature and less time. What gives?
The answer is that in the oven, the air temperature is 300°F, but that doesn't mean that the temperature of the sauce is actually 300°F. Indeed, you'll find that, other than on the very surface, most of the sauce doesn't ever heat up beyond around 200°F or so. The vast majority of the darkening that occurs in an oven occurs only at the surface of the sauce, which means you need a decent amount of time to darken it enough to flavor the whole batch.
A pressure cooker, on the other hand, heats its entire contents to 250°F. That's the sauce at the top, the bottom, and everything in between. Browning occurs more evenly, as well as over a greater volume, so it takes less time overall.
Remember, liquids don't really reduce in a pressure cooker, which means that the final flavor of a pressure-cooked sauce is not quite the same as that of an oven-cooked sauce. But, unless you're doing a direct, side-by-side comparison, it's not something you or your dinner companions are likely to notice.
That's a sacrifice I'm willing to make to be able to eat this stuff any day of the week.
And remember: The greatest sauce in the world ain't worth a damn if you don't sauce that pasta the right way!