Adjust rack to middle position and preheat oven to 425 degrees. Line a baking sheet with foil and lightly oil (or coat with nonstick cooking spray). Wash and dry produce.

Halve, peel, and thinly slice half the onion (whole onion for 4 servings). Zest and quarter lime (for 4, zest one lime and quarter both).

In a small bowl (medium bowl for 4 servings), combine 1½ TBSP sliced onion (3 TBSP for 4), juice from half the lime, and a pinch of salt.

In a separate small bowl, combine Mexican cheese blend and Monterey Jack.

Open and drain tofu; press out excess water with paper towels.

Dice tofu into ½ inch cubes. Add to a medium bowl with Southwest Spice Blend, cornstarch, and a big pinch of salt and pepper. Toss until evenly coated.

Heat a large drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Once pan is hot, add tofu in an even layer; cook, undisturbed, until lightly browned on bottom, 2-3 minutes. 

Add remaining sliced onion; cook, stirring occasionally, until onion is slightly softened and tofu is browned, 3-4 minutes more (if pan seems dry, add another drizzle of oil).

Stir in Tex-Mex paste and ⅓ cup water (½ cup for 4 servings). Simmer until thickened, 1-2 minutes. Turn off heat.

Meanwhile, drizzle tortillas with 1 TBSP oil (2 TBSP for 4 servings); brush or rub to coat both sides.

Place tortillas on a clean work surface. Once filling is done, add a heaping ¼-cup scoop to one side of each tortilla; sprinkle with 1 TBSP cheese mixture. Roll up tortillas, starting with filled sides, to create taquitos. Place, seam sides down, on prepared sheet. TIP: Make sure the taquitos are snug on the sheet—this will prevent them from unrolling.

Bake on middle rack until golden brown and crispy, 8-12 minutes.

While taquitos bake, finely dice tomato. Add tomato and half the lime zest to bowl with pickled onion. Toss to combine and season with salt.

In bowl used for cheese, combine guacamole, sour cream, remaining lime zest, and a squeeze of lime juice. Season with salt and pepper.

Divide taquitos between plates. Top with creamy guacamole and pico de gallo. Serve with any remaining lime wedges on the side.