Preheat the oven to 400 degrees F. Line a sheet pan with parchment paper.
For the rice, bring a large pot of water to a boil over high heat. Add the rice and continue boiling until the rice is tender, about 35-55 minutes. The rice should be tender with a chewy bite. Drain the rice and put it back in the pot. Then let it rest for 10 minutes and fluff it with a fork. (You can spread it across a plate to get it to cool down faster.)
On the prepared pan, toss the pumpkin with 1 tablespoon olive oil, 1/2 teaspoon kosher salt and 1/4 teaspoon black pepper. Spread the cubes into single layer.
Roast the pumpkin for 30-35 minutes until it is tender in the middle and lightly browned on the edges.
To make the vinaigrette, whisk the garlic, maple syrup, mustard, 1/2 teaspoon kosher salt, 1/4 teaspoon black pepper, balsamic vinegar and 1/4 cup olive oil in a small bowl.
In a large bowl, toss the rice and kale with half the vinaigrette.
Stir in the roasted pumpkin, red onions, walnuts, parmesan and parsley, drizzling in more dressing as desired.