Carefully rinse the rice (sifting through for any impurities). Drain thoroughly. In a medium pot, combine the rice, a big pinch of salt, and 1 cup of water (or 2 cups of water for 4 servings). Heat to boiling on high. Once boiling, reduce the heat to low. Cover and cook, without stirring, 13 to 15 minutes, or until the water has been absorbed and the rice is tender. Turn off the heat and fluff with a fork. Cover to keep warm.

Meanwhile, wash and dry the fresh produce. Remove any husks and silks from the corn; cut the kernels off the cobs. Halve the tomatoes. Halve the lime(s) crosswise. In a bowl, combine the halved tomatoes, the juice of 1 lime half (or 2 halves for 4 servings), and a drizzle of olive oil. Set aside to marinate, stirring occasionally. Taste, then season with salt and pepper if desired.

In a medium nonstick pan (or large for 4 servings), heat a drizzle of olive oil on medium-high until hot. Add the corn kernels in an even layer. Cook, without stirring, 3 to 4 minutes, or until lightly charred (be careful, as the corn may pop as it cooks). Add up to half the spice blend, depending on how spicy you'd like the dish to be. Cook, stirring constantly, 30 seconds to 1 minute, or until combined and the corn is coated. Transfer to a bowl. Cover with foil to keep warm. Rinse and wipe out the pan.

In the same pan, heat a drizzle of olive oil on medium-high until hot. Add the beef; season with salt and pepper. Cook, stirring frequently and breaking the meat apart with a spoon, 2 to 3 minutes, or until lightly browned. Carefully drain off and discard any excess oil. Add the guajillo sauce (carefully, as the liquid may splatter) and 1/4 cup of water (or 1/2 cup for 4 servings); season with salt and pepper. Cook, stirring occasionally, 3 to 4 minutes, or until the sauce is slightly thickened and the beef is cooked through. Turn off the heat. Taste, then season with salt and pepper if desired.

Meanwhile, in a bowl, combine the mayonnaise, the juice of the remaining lime half (or remaining lime halves for 4 servings), and as much of the remaining spice blend as you'd like; season with salt and pepper. Serve the cooked rice topped with the cooked beef, cooked corn, and salsa. Drizzle with the lime mayo. Garnish with the cotija. Enjoy!