Heat large skillet over medium; drizzle with olive oil.
Add veggies once oil shimmers. Season with salt, pepper, and oregano. Allow to fully cook, 7-8 minutes.
Carefully add broth, scraping the bottom of pan and mixing veggies. Stir in soy sauce and continue to cook for 1 minute.
Place open rolls on a baking sheet. Add veggies to each roll and top with cheese. Toss in oven for 2-3 minutes or until cheese melts and bun becomes a little toasty.