Preheat the oven to 200C/390F.
Dice the onion; cut the carrot in half, and again in half just through the middle in quarters, and then into bite-sized pieces.
Rinse the rice with cold water not more than 2-3 times. (This step should be done right before adding the rice to the pan)
Preheat a nonstick pan over medium heat. Add olive oil together with the onion and carrot. Cook for 3-4 minutes or until the vegetables are soft. Continue and add the rice and cook for another 2 minutes while stirring every 30 seconds.
Add the vegetable stock or water along with the seasonings. Bring the rice to simmer, cover with aluminium foil then transfer it to the oven.
Once the rice gets to a boil again, lower the temperature to 180C/355F and boil for 10 minutes or until the rice is cooked and all the water is gone.
Take the pan out of the oven, fluff the lentils with a fork, put the lid on, and let it steam for 10-15 minutes.