Finely dice the onion, tomato, and jalapeño. Keep them in separate bowls for now.
Heat the skillet over medium-high heat and add the olive oil
Once the olive oil is hot, add the onions to the skillet, sprinkle with a pinch of salt. Sauteé for 5 minutes or until translucent.
Add the jalapeño, sprinkle with salt, and sauteé for 3 more minutes
Add the tomato, sprinkle with salt, and sautée for 5 more minutes, or until all vegetables are soft.
While the onion mixture is cooking, chop the zucchini into 1" pieces. I like to chop them into quarter circles.
Add the zucchini to the onion mixture
Sprinkle with adobo and oregano. Stir to fully combine
Let mixture cook for 5 more minutes or until zucchini is fully soft. Taste and adjust seasoning as needed. Serve.