About us Ontar Thai Restaurant is a family-run restaurant. Founded in 2013, this small restaurant in Ontario city. Has a laid-back atmosphere, perfect for lunch and dinner. There are many Thai restaurants in Southern California. Serving delicious Thai food. Ontar Thai Restaurant is another restaurant that serves authentic Thai food prepared by a secret family recipient that has been passed down by our ancestors. We are located in the Airport Gateway Plaza, cross the 10 freeway, pass the traffic light intersection, turn right into Plaza. The shop is on the left-hand side next to One Main Financial. If you've never eaten Thai food before, we want you to be sure that not every dish is as spicy as you think. Everything, seasoned as desired with Spice Scale from 0 - 5.