Preheat your oven to 400 degrees.
Mix the olive oil and seasonings in a bowl.
Clean and prep your red potatoes.
Cut your potatoes in half then in quarters.
Place your potatoes in a bowl. Add 1/2 tablespoon of the olive oil dressing and mix.
Place the potatoes on to a baking sheet.
Place the potatoes into the oven for 15 minutes.
Clean and prep your remaining vegetables.
Cut the zucchini and squash to medium-thin slices. Cut your brussels sprouts in half.
Place your vegetables into a medium sized bowl and pour the remaining olive oil dressing over the vegetables and mix.
After 15 minutes, remove the potatoes from the oven and flip them so that they can cook evenly.
Add the remaining vegetables to the baking sheet and mix them with the potatoes.
Roast all of the vegetables for 15 minutes. After 15 minutes, flip the vegetables over using a spatula so that they can cook evenly.
Return the vegetables to the oven and continue to roast for 10 minutes.
Remove the vegetables from the oven and season with additional oregano and salt and pepper to taste.
Serve.