Preheat oven to 350°. Place strawberries on a parchment-lined rimmed baking sheet. Sprinkle with sugar and toss to coat. Bake until just tender, 35-40 minutes. Cool slightly.
Meanwhile, grease a 15x10x1-in. baking pan. In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in extract. In another bowl, whisk flour, baking powder and salt; add to creamed mixture alternately with milk, beating well after each addition (batter may appear curdled).
Transfer to prepared pan. Top with 3 cups roasted strawberries; sprinkle with turbinado sugar. Reserve remaining strawberries for serving. Bake until a toothpick inserted in center comes out clean, 30-35 minutes. Cool completely in pan on a wire rack. Serve with reserved roasted strawberries.