Position top oven rack in the center position.
Pre-heat oven to 350°F.
Spray a medium-sized baking dish with non-stick cooking spray. Set aside.
In a large bowl, whisk together eggs and half & half.
Add 1/2 of the Gouda cheese. Stir to combine. Set aside.
Place 1 tablespoon olive oil in a large skillet.
Place skillet over medium heat and heat until oil is hot.
Add sweet potato, red pepper, onion, garlic powder, basil and parsley.
Season with salt and black pepper, to taste. Stir to combine.
Cook, stirring occasionally, until the pepper and onion soften and the sweet potato starts to develop a bit of color, about 5 - 6 minutes.
Remove from heat and transfer mixture to the prepared baking dish. Spread into a uniform layer. Set aside.
Add the remaining olive oil to the same skillet.
Place back over medium heat.
Toss in the arugula or spinach. Cook, stirring occasionally, just until the greens wilt, approximately 2 - 3 minutes.
Remove from heat and spread evenly on top of the other vegetables in the baking dish.
Pour egg mixture on top and spread with a rubber spatula, if necessary, to cover the entire surface.
Sprinkle remaining cheese on top.
Season with additional salt and black pepper, if desired.
Place dish in pre-heated oven. Bake until egg is set and the top starts to turn golden brown, about 25 - 30 minutes.
Remove from oven and cool slightly before slicing.
Garnish with fresh herbs, if using, and serve immediately.