How to Make It
Preheat oven to 400°.
To prepare crust, weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine flour, 1 1/2 tablespoons nuts, 1/4 teaspoon salt, 1/4 teaspoon pepper, and baking powder in a food processor; pulse 3 times to combine. Combine 1/4 cup oil and 3 tablespoons water in a small bowl. With processor on, slowly add oil mixture through food chute; process until dough is crumbly. Sprinkle dough into a 9-inch pie plate coated with cooking spray. Press dough evenly into bottom and up sides of pie plate. Bake at 400° for 23 minutes or until lightly browned.
Combine squash and 1 teaspoon oil on a baking sheet coated with cooking spray; toss. Bake at 400° for 25 minutes, stirring once.
Heat a large nonstick skillet over medium heat. Add remaining 1 tablespoon oil to pan; swirl to coat. Add onion and garlic; sauté 7 minutes. Add chard, vinegar, 1/2 teaspoon salt, and 1/4 teaspoon pepper; cook 3 minutes or until chard wilts. Combine chard mixture, eggs, and 2 ounces cheese in a large bowl. Add squash and remaining half of nuts; toss gently to coat.
Pour the squash mixture into crust, and sprinkle with the remaining cheese. Bake tart at 400° for 23 minutes or until filling is set.