Cellentani with Chicken Hearts and Spinach

I've been making lots of Asian food lately, so naturally I needed to cook some pasta to balance things out. I knew I wanted to use cellentani (one of my faves) and some combination of chicken livers and spinach. Couldn't find any chicken livers, but got some jidori chicken hearts at Mitsuwa, our local Japanese supermarket. It was my first time cooking chicken hearts and it surprisingly came out tender with a very meaty flavor. Whenever cooking something for the first time, cook a small batch first to see if any adjustments need to be made to seasoning or cooking technique. It definitely helped, as I found searing it on both side quickly leaves a very tender and flavorful chicken heart. A very, very fun dish to eat and don't worry - chicken hearts tastes like dark chicken meat, but with a richer flavor and more chewy texture.

Ingredients (all are guesses, since I never measure)
1/2 pound jidori chicken hearts, soaked in water for at least a half hour, then drained
1/4 pound jidori chicken thighs, bone in
1/2 box cellentani
5 cloves garlic thinly sliced
1 small onion thinly sliced
4 cups baby spinach
Extra Virgin Olive Oil
Grated parmiggiano reggiano
2 tbsp balsamic vinegar
Salt and pepper

1) Add sliced onions to a saute pan, salt/pepper, add some olive oil, and set to medium heat. Caramelize the onions - basically cooking over medium heat for 5-10 minutes and stirring occasionally making sure onions don't burn. Remove onions and set aside for later.
2) Salt and pepper the chicken thighs on both sides, add the chicken skin side down to the same pan you cooked the onions in. After the skin gets very crisp (5-10 minutes), flip the chicken over to the other side.
3) After another 5 minutes, move the chicken to the very edge of the pan turning on a side that hasn't touched the pan yet. Now, there should be plenty of chicken fat in the pan to cook the hearts in.
4) Set large pot of water to high heat. When the water comes to a boil, salt the water heavily and drop the pasta in. This could be done between steps 2 and 3.
5) Add chicken hearts to the saute pan and season with salt and pepper. After 1-2 minutes, flip the chicken hearts as they should be nicely seared on one side. Cook for another 1-2 minutes on the other side and cut the heat to low.
6) Add spinach, garlic, caramelized onions, and balsamic vinegar (for some sweetness and a contrast of flavors), season with salt/pepper, turn a couple times gently, and cover. This should only cook for 3-4 minutes max on low heat.
7) After 10 minutes of pasta cooking time, take the pasta out and add to the pan. Cook for one minute, cut the heat, add 1/3 cup olive oil and taste. May need to add more salt and pepper. If it's too dry, add some pasta water. If it's too watery, cook it down some more. There should be a rich flavorful, slightly sweet, brown sauce from the hearts and chicken thighs that clings to the pasta. Serve immediately and add healthy coating of parmiggiano-reggiano. Buono appetito!