Start by browning the ground beef, chicken, or turkey in a large skillet. You will know it is done when there is no pink left and it smells savory. This step builds the flavor base for the whole casserole. Just be careful not to overcrowd the pan, or your meat might steam instead of brown.
Next, sprinkle in the taco seasoning and stir it well with the meat. The spices should cozy up to the meat, making everything aromatic and flavorful in no time. Avoid leaving any dry seasoning clumps, as they will not distribute well later.
Stir in the pasta shells and pour in the water. You will notice the pasta is just covered, and it should look like a bubbling pot of goodness. Water helps cook the pasta while flavors meld together. Just be cautious with the heat; you do not want it to boil over!
Pour the salsa into the mix and give it a good stir. You should see the beautiful colors from the salsa blending with the meat and pasta. This adds both moisture and tang to your dish. Make sure to scrape the bottom to avoid any bits sticking, which could burn.
Let it all simmer until the pasta is al dente, which will take a few minutes. You will know it is ready when the pasta is tender but still has a bite. This is crucial so it holds up during baking. Keep an eye on it; overcooked pasta can get mushy.
Sprinkle the shredded cheese on top and give it a little mix. The cheese should melt into everything, creating a lovely stretchy top layer. This step adds creaminess and a nice finishing touch. Just do not skip this step if you are a cheese lover!
Transfer the mixture to a baking dish and pop it into the oven. You will want it to bake until the edges are golden and bubbly. This helps all the flavors meld together beautifully. Do not forget to cover with foil if you are worried about it drying out!
Once it is out of the oven, let it rest for a few minutes. This allows everything to set, and you will not burn your fingers! You will want to scoop it into bowls and maybe even top with a sprinkle of extra cheese.