Step 1

In a large bowl, whisk together the oil, lemon juice, mayonnaise, mustard, garlic, red pepper flakes, salt and black pepper until smooth.

Step 2

In a medium (3- or 4-quart) pot over medium-high heat, combine the rice with enough water to cover by 2 inches. Bring to a boil, then reduce the heat to medium-low, so the liquid is at a simmer, and cook, uncovered, until the rice is barely tender but not mushy, 7 to 9 minutes. Drain and transfer the rice to the bowl with the dressing, stir to combine, and let cool slightly while you prep the vegetables.

Step 3

In a food processor, combine the zucchini, bell pepper, celery, arugula, olives and parsley. Being careful not to overprocess, pulse several times until everything is about the size of a grain of rice, scraping the sides of the food processor bowl as needed. Transfer to the bowl of rice.

Step 4

Add the beans and tomatoes to the bowl, and gently fold to combine. Taste, and season with more salt and black pepper, as needed.

Step 5

Transfer to a serving platter or shallow bowls, drizzle with more oil and serve at room temperature, or chill and serve cold.