Wash and dry all produce. Core and seed bell peppers, then thinly slice. Halve and peel onion. Thinly slice one half. Finely dice other half. Zest 1 tsp zest from limes, then cut each into quarters. Halve and thinly slice half the jalapeño; finely dice other half. TIP: Remove the ribs and seeds first for less heat.

In a small bowl, combine lime zest, sour cream, 2 tsp water, and a squeeze of lime (to taste). Season with salt and pepper.

In another small bowl, toss together sliced jalapeño, juice of one lime quarter, a pinch of salt, and sugar to taste (we used 1/4 tsp sugar).

Heat a large drizzle of oil in a large pan over medium-high heat. Add bell peppers and cook, tossing, until beginning to soften, 2-3 minutes. Add sliced onion and cook, tossing often, until tender and lightly charred, 5-6 minutes. Season with salt and pepper. Remove from pan and set aside.

Lower heat under same pan to medium and add a large drizzle of oil and diced onion. Cook, stirring, until softened, 2-3 minutes. Stir in Southwest spice and diced jalapeño (to taste). Cook until fragrant, about 30 seconds. Add beef and break it up into pieces with a wooden spoon. Cook, tossing occasionally, until browned and cooked through, 4-5 minutes. Season with plenty of salt and pepper.

Wrap tortillas in a lightly dampened paper towel and microwave on high until warm and soft, about 30 seconds. Divide beef, bell peppers, onion, and cheese between tortillas. Dollop with crema. Tear cilantro leaves from stems and scatter over top. Garnish with marinated jalapeño (to taste). Serve with lime quarters on the side.