To prepare crust, weigh or lightly spoon 25 ounces flour (about 1 2/3 cups) into dry measuring cups; level with a knife. Combine 25 ounces flour, 1/2 teaspoon salt, and baking powder in a food processor; pulse 2 times to combine. Combine 1/3 cup olive oil and 1/4 cup water in a small bowl. With processor on, slowly add oil mixture through food chute, and process just until dough begins to form a ball (dough will be crumbly). Turn dough out onto a lightly floured surface. Knead 3 minutes; add enough of the remaining 2 tablespoons flour to prevent dough from sticking to hands. Divide dough into 2 equal portions. Press each portion into a 5-inch circle on plastic wrap. Cover with additional plastic wrap. Chill at least 30 minutes.
To prepare torta, preheat broiler to high.
Cut bell peppers in half lengthwise; discard seeds and membranes. Place pepper halves, skin sides up, on a foil-lined baking sheet; flatten with hand. Broil 10 minutes or until blackened. Place in a paper bag; fold to close tightly. Let stand 10 minutes. Peel and coarsely chop.
Heat a large nonstick skillet over medium heat. Add 1 tablespoon oil; swirl to coat. Add chard to pan; cook 1 minute or until greens begin to wilt. Place chard and bell peppers in a large bowl. Return pan to medium heat. Add remaining 1 tablespoon oil to pan; swirl to coat. Add shallots and garlic to pan; cook for 1 minute. Add mushrooms; cook 5 minutes, stirring occasionally. Place mushroom mixture and chard mixture in a fine sieve; let drain 5 minutes. Place vegetable mixture in a large bowl. Add ricotta and next 7 ingredients (through egg white) to vegetable mixture, stirring to combine.
Preheat oven to 375°.
Slightly overlap 2 sheets of plastic wrap on a slightly damp surface. Unwrap one dough portion, and place on plastic wrap. Cover dough with 2 additional sheets of overlapping plastic wrap. Roll dough, still covered, into an 11-inch circle. Place the dough in freezer for 5 minutes or until plastic wrap can be easily removed. Remove top sheets of plastic wrap; fit dough, plastic wrap side up, into a 9-inch pie plate coated with cooking spray. Remove remaining plastic wrap. Spoon vegetable mixture into prepared pie plate.
Slightly overlap 2 sheets of plastic wrap on a slightly damp surface. Unwrap remaining dough portion, and place on plastic wrap. Cover dough with 2 additional sheets of overlapping plastic wrap. Roll dough, still covered, into an 11-inch circle. Place the dough in freezer for 5 minutes or until plastic wrap can be easily removed. Remove top sheets of plastic wrap; fit dough, plastic wrap side up, over vegetable mixture. Remove remaining plastic wrap. Press the edges of dough together. Fold edges under, and flute. Brush top of dough with milk. Cut several slits in top of dough to allow steam to escape.
Bake at 375° for 45 minutes or until crust is golden brown. Cool 30 minutes. Cut into 8 wedges.
Wine Match: This veggie-packed dish deserves an earthy Italian red. Banfi's Centine Rosso 2009 ($11) has flavors of tart cherries and, to complement the pizza's shallots, garlic, and thyme, undertones of oak and spices. --Gretchen Roberts
Quick Dough Trick: For fast pizzas, we like to use refrigerated dough from our grocer's bakery section and let it stand at room temperature for 15 minutes to make it easier to roll. But when there isn't time to spare, try this trick: Put the dough in a bowl, and microwave at HIGH for 30 seconds or 50% power for 45 seconds. If the dough shrinks or snaps back as you roll it out, let it rest for several minutes--the gluten will relax, letting it stretch to the desired size.