The box of instant au gratin potatoes from the supermarket advertises a dish &ldquo;made with 100 percent real cheese and potatoes.&rdquo; But the potatoes are dehydrated and the cheese sauce is powdered.</p><p>Read the ingredient list and you&rsquo;ll find lots of hard-to-pronounce, scientific-sounding words. Check out the nutrition facts and you&rsquo;ll discover most processed foods contain a fair amount of sodium.</p><p>No thanks.</p><p>On the flip side, homemade au gratin can drown out the positive nutritional value of potatoes with a lavish dose of heavy cream and cheddar cheese. Flipping through the current issue of Country Living magazine proves the point: a recipe with 23.6 grams of fat and 780 milligrams of sodium per serving.</p><p>So what&rsquo;s a conscientious cook to do? </p><p>The Star&rsquo;s <strong>Au Gratin Potato Casserole </strong>uses reduced-fat dairy products to trim the fat and calories from this creamy, satisfying comfort food that few of us would be willing to banish from the dinner table.</p><p>Potatoes are an excellent source of potassium, niacin and minerals. Potatoes also contain good amounts of vitamins B6 and C, and the skin is rich in fiber and iron. </p><p><strong>&bull;Shopping tip:</strong> Red-skinned potatoes are waxier and hold their shape better than russets when boiled. </p><p><hr class="infobox-hr-separator" /> <div class="infobox"> <strong><span class="subhead">Au Gratin Potato Casserole</span></strong></p><p>Makes 12 servings</p><p>2 pounds red-skinned potatoes, not peeled (about 5 to 6 medium)</p><p> 1/4 cup very finely chopped onion</p><p>2 cloves garlic, minced</p><p>2 tablespoons all-purpose flour</p><p>1&ensp; 1/2 cups fat-free skim milk</p><p> 1/8 teaspoon salt</p><p> 1/8 teaspoon pepper</p><p>2 tablespoons minced flat-leaf (Italian) parsley, minced, divided</p><p>1 cup reduced-fat shredded cheddar cheese</p><p>2 tablespoons shredded Parmesan cheese</p><p>Scrub potatoes and remove eyes. Cut larger potatoes in half. Place potatoes in large saucepan and add cold water to cover. Cover pan and heat over high heat until water boils. Reduce heat and cook until potatoes are tender, about 30 to 40 minutes. Drain potatoes and set aside to cool slightly.</p><p>Preheat oven to 350 degrees. Spray an 11-by-7-inch (2-quart) casserole dish with nonstick spray coating. </p><p>Combine onion, garlic, flour, milk, salt and pepper in a medium, heavy saucepan. Whisk thoroughly, blending until the flour is completely dissolved. Heat over medium-low heat, whisking constantly, until milk is bubbly and slightly thickened. Remove from heat. Whisk in 1 tablespoon parsley and the cheddar cheese; stir until cheese is blended. </p><p>When potatoes are just cool enough to handle, peel and slice 1/4 -inch thick. Place sliced potatoes in prepared casserole dish. Drizzle cheese sauce over potatoes, covering slices evenly and completely. Sprinkle with Parmesan cheese. Bake 20 to 30 minutes or until hot and golden. Sprinkle with remaining parsley just before serving.</p><p><em>Per ( 1/2 -cup) serving: 117 calories (8 percent from fat), 1 gram total fat (1 gram saturated), 3 milligrams cholesterol, 21 grams carbohydrates, 6 grams protein, 116 milligrams sodium, 2 grams dietary fiber. </em></p><p></div>