Bring a large pot of water to a boil. Cook the pasta according to package directions until al dente.
Drain the pasta and then rinse under cool water. Transfer the pasta to a large serving bowl and toss with some oil to prevent sticking while you prepare the veggies.
Cut each tomato in half lengthwise and add on top of the pasta.
Core and seed the bell pepper. Dice the pepper and add it to the pasta bowl.
Remove the skin from the onion, cut the onion almost in half (so there are 2 quarter pieces that touch at the root), and then thinly slice the onion. Rinse the onion under cold water and separate into strips. Dry with a paper towel and add to the pasta bowl.
Remove the stem from your broccoli and then cut the tops into small, bite-sized pieces. Add to the pasta bowl.
Place all the dressing ingredients into a mason jar or medium bowl. Shake or stir until combined.
Pour the Italian dressing over the vegetables and pasta. Use a wooden spoon to gently toss everything together until well coated in the dressing.
Cover and refrigerate until ready to serve.
You can substitute your favorite Italian dressing in this recipe as well. I love a good roasted red pepper Italian dressing.