Slice sausage at an angle to about 1/2-1 inch slices with a knife. Set aside
Preheat a large skillet or wok to high heat. Add cooking oil and swirl to coat the skillet. Add onion and stir fry for 2 minutes. Add mixed veggies followed by red curry paste. Stir fry for another minute. Add sausages and stir fry for about 30 seconds. Add the rice and stir to mix everything. The rice will pick up the red color from the red curry paste
Have a taste and season with salt to your taste. Add basil leaves. Turn off the heat. Stir to mix everything. The residual heat will continue to soften the basil leaves without overcooking them