Preheat oven to 350ºF. Lightly spray a 9×13-inch baking dish with cooking spray. Set aside.: You should feel the warm kitchen air as the oven climbs to 350ºF , and preheating ensures even baking, so the center comes up to temperature as the top browns. A lightly greased 9×13 inch baking dish prevents sticking and helps create gentle browning along the edges. One common mistake is not preheating fully, which can lead to uneven baking and a longer cook time, so wait until the oven indicates it has reached temperature.
Prepare rice according to package directions.: As the boxed yellow rice simmers, you will notice steam and a fragrant, seasoned aroma that signals it is cooking through. Fluff with a fork when done to keep grains separate, which will help the casserole avoid a gummy texture. If rice is overcooked or too wet, it can make the casserole dense, so drain any excess liquid and allow the rice to cool slightly before combining.
Combine cooked rice, cooked chicken, chili, cream cheese, and salsa.: When you mix these elements, you should see creamy swirls of softened cream cheese and bits of shredded chicken folded into seasoned rice . The aroma will be layered, with tang from the salsa and savory depth from the canned chili . Stir until the cream cheese is fully incorporated for uniform creaminess. Avoid under mixing, which can leave pockets of unmelted cheese, and over mixing, which may break down the chicken too much.
Spread chicken and rice into the prepared baking dish. Top with shredded cheese.: Press the mixture evenly into the dish so it bakes uniformly, and sprinkle the 2 cups of shredded Mexican cheese blend across the top for even melting. You will see the cheese begin to soften quickly as it sits on the warm mixture, and during baking it will turn golden and bubbly. A common misstep is piling cheese too thickly in one spot, which can cause uneven browning, so distribute it evenly across the surface.
Bake for 35 to 45 minutes, until bubbly. Garnish with chopped green onions.: As the casserole bakes, listen for gentle bubbling at the edges and watch the top turn a golden, slightly crisped cheese color. The scent will intensify, with creamy and spicy notes melding together. Baking time may vary depending on how cold the casserole was when it went into the oven, so if assembled cold add a few extra minutes. A typical mistake is removing it too early, which leaves the center underheated, so use bubbling and a golden top as your cues. Finish with a scatter of chopped green onions for freshness and color contrast.
