Sauté in a little olive oil over medium heat for at least 3 minutes the onion. Then add the cherry tomatoes, salt, pepper, and oregano.
With a fork and as the cherry tomatoes begin to soften push them to get their liquids. This process will take about 10 minutes.
At the same time, heat the broth. Once the tomatoes have softened, remove them from the pan, then add the rice and sauté for 2-3 minutes.
Add the glass of white wine and mix until the alcohol evaporates.
Then add 2-3 tablespoons of warm broth and mix with a wooden spoon. Once the broth is absorbed, add gradually the broth and repeat until the rice is ready (about 18 minutes).
Before adding the last tablespoon of the broth, add the cherry tomatoes to the pan again.
Once the rice is ready, remove from the heat and pour the butter, parmesan, salt, and pepper.
With a wooden spoon, mix well and leave the risotto for 2 minutes to rest.
Serve immediately after and add some parmesan and pepper on top.