In large skillet, toast pumpkin seeds over medium-high heat, stirring frequently, until golden brown. Pour onto plate to cool and set aside.
In bowl, place berries, basil, vinegar, and maple syrup, and stir gently to coat. Set aside and allow to marinate for about 30 minutes. After time has elapsed, into large bowl, strain any liquid and add one or two raspberries, reserving the remainder.
Mash the two raspberries in liquid in large bowl, add olive oil and salt, and whisk together. Add red onion and greens and toss to coat. Arrange on large platter, placing reserved marinated berries on top. Sprinkle with pumpkin seeds and serve.
Enjoy!