Yes you can buy them already made at the store… but there are few things that can compare to the nurturing and filling sensation of homemade corn tortillas.
Makes about 10 to 12 tortillas
2 cups corn tortilla flour, such as MASECA
1 3/4 cup water (or enough to achieve a play dough consistency dough! varies with climate)
Set a comal or ungreased dry skillet over medium heat, for at least 5 to 8 minutes, until hot.
To make masa or dough, pour 1/4 cup water into a large mixing bowl so the flour will not stick to the bottom of the bowl once you mix it in. Slowly add the corn tortilla flour and the rest of the water as you knead the masa in a circular motion. Do so for a couple minutes, until it is smooth and has no lumps. If it feels too dry, add a bit more water. Masa dries out fast, so if you leave it unattended, cover it with a clean moist kitchen towel or cloth.
To make the tortillas, divide the dough into 1 1/2″ balls. Cut out 2 plastic circles from a thin plastic bag, like ones you get at grocery stores. With one ball at a time: Place one plastic circle in the bottom of the tortilla press and place the masa ball on top. Place the other plastic circle on top of the ball and press down the press, to make a flat disk. Open the press, take the top plastic off, lift the bottom plastic with the tortilla in one hand and peel the tortilla from the plastic with the other hand. Alternatively, you can place a ball between plastic pieces and roll the tortillas out with a rolling pin.
Place the tortilla on the hot comal or skillet. Let it cook for about 30 seconds, or as soon as it can be flipped without sticking to the comal, and it becomes opaque on the side that it was cooking on. Turn over and cook for about a minute, until opaque and starting to freckle on the other side. If it is opaque but it has white-ish areas, you need to leave it a bit more, until those white-ish shadows become freckled with brown spots. Turn over once more, and now, after a couple seconds, tortilla should puff up like pita bread, if not all over tortilla, at least in an area of it. Let the tortilla cook still, for about 10 seconds, so that it cooks in between the area that puffed up.
If eaten that same day, tortillas may be kept wrapped in a clean kitchen towel or cloth. If not, wrap in a kitchen towel, inside a closed plastic bag and place in the refrigerator. They will keep for up to 3 days, afterwards they will turn too hard. Reheat in hot comal for 30 seconds or so on each side before eating. They can also be frozen and kept for months.