Preheat the oven to 400 degrees F.
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 a sheet pan, toss the corn and tomatoes with 1 tablespoon olive oil, 1 teaspoon kosher salt and 1/2 teaspoon black pepper. Spread them into a single layer across the pan, arranging the tomatoes, so they are cut side up.
Roast the corn and tomatoes for 30-35 minutes until the corn is golden brown on the edges and the tomatoes are wrinkled.
While the vegetables are in the oven, make the vinaigrette. Whisk the garlic, mustard, 1/2 teaspoon kosher salt, 1/4 teaspoon black pepper, red wine vinegar, lemon juice and 1/4 cup olive oil in a small bowl.
To assemble the salad, combine the rice and kale in a large bowl. Pour in half the dressing, stirring to combine.
Fold in the roasted corn and tomatoes, scallions, walnuts and parsley, drizzling in more dressing as desired.