Winter stews depend on long, slow cooking to develop flavor. Spring and summer meals, however, are best cooked quickly or not at all. You want ingredients to enhance one another, not blend. That means the staples you use to season a baby-lettuce salad or a steak from the grill must be first-rate. So don't mindlessly grab any old chicken broth, salt, and Parmesan off the shelf. Follow the number one rule of all professional chefs: High-quality basics are the building blocks of high-quality meals. And they're worth going out of your way to find. Study this list before your next grocery-shopping trip. You may spend a little extra at the checkout, but you'll taste the payoff in every bite.

BLACK PEPPER

Pepper is one of the last things you add to a dish, so its flavor has a big impact. Always grind your own.
The upgrade: Tellicherry black peppercorns ($4 for a four-ounce bag, www.penzeys.com).

BUTTER

Use creamy European-style butter on the rare occasions you use butter for cooking. Buy unsalted to control the sodium.
The upgrade: Organic Valley, Horizon Organic, or Land O' Lakes Ultra Creamy Butter ($3 to $3.50 for eight ounces, in supermarkets).

CANNED TOMATOES

Organic tomatoes come in enamel-lined cans, so there's no metallic taste — just a fresh, natural flavor.
The upgrade: Muir Glen Organic tomatoes ($1.50 for 14.5 ounces, in most supermarkets and health-food stores).

CHICKEN BROTH

Broth from bouillon cubes is overly salty and suspiciously yellow. Low-fat, low-sodium broth is ideal.
The upgrade: Swanson Natural Goodness 100% Fat Free ($3 for 32 ounces, in supermarkets).

EGGS

Spring for organic eggs from free-range chickens. The yolks are bright yellow-orange, not a muted yellow, and the taste is full, rich, and downright eggy.
The upgrade: Greenbrier or Trader Joe's ($2.50 to $3.50 a dozen, at health-food stores or Trader Joe's, www.traderjoes.com for store locations).

EXTRA-VIRGIN OLIVE OIL

There is a huge difference in quality between the big-brand varieties and oils made by small producers. A flavorful extra-virgin olive oil can transform a simple salad into something spectacular.
The upgrade: Lucini Italia ($14 for 500 milliliters, www.happycookers.com) or Bertolli Gentile ($6 for 500 milliliters, in supermarkets).

PARMESAN

Bypass the canned version. The best-tasting Parmesan is from a specific region in Italy and has the Parmigiano-Reggiano stamp on its rind.
The upgrade: Authentic Parmigiano-Reggiano ($9 to $18 a pound).

PEANUT BUTTER

The kids' stuff is loaded with sugar. The natural kind contains only peanuts and salt.
The upgrade: Smucker's Natural Creamy Peanut Butter ($3 for 16 ounces, in supermarkets).

SALT

Kosher and sea salt are clean-tasting and easy to control with your fingers.
The upgrade: Maldon Sea Salt ($4.50 for 8.5 ounces, www.thespicehouse.com) or Diamond Crystal Kosher Salt ($2 for three pounds, in supermarkets, or call 800-428-4244).

TUNA

Italian-style light-meat tuna packed in olive oil delivers a double dose of good fats. It has more calories than the all-white-meat, water-packed kind, but it doesn't need a lot of mayo when made into tuna salad.
The upgrade: Genova ($2 for six ounces, in supermarkets).

VANILLA

Use pure (not imitation) vanilla extract and you'll be wowed by its complex, heady perfume.
The upgrade: Nielsen-Massey Madagascar Bourbon Pure Vanilla Extract ($19 for four ounces, www.kingarthurflour.com) or McCormick Pure Vanilla Extract ($7 for four ounces, in supermarkets).