01 - Preheat the oven to 350°F. Line a 9x13 inch baking pan with parchment paper.
02 - In a large bowl, mix together zucchini, carrot, bell pepper, and red onion.
03 - Incorporate the shredded cheddar, parsley, and chives into the vegetable mixture, stirring thoroughly.
04 - In a separate bowl, whisk the eggs with olive oil until fully blended.
05 - Pour the egg mixture over the vegetables and cheese, stirring to combine evenly. Sprinkle in the whole wheat flour, baking powder, salt, and black pepper. Gently mix until just combined; avoid overmixing.
06 - Spread the mixture evenly in the prepared pan, smoothing the surface.
07 - Bake for 30 to 35 minutes until the top is golden and the center is set.
08 - Allow bars to cool in the pan for 10 minutes. Lift out using the parchment paper, cut into 12 bars, and serve warm or at room temperature.