Place a medium-sized saucepan over a medium heat and add the butter. Watch it as it melts into a golden pool, then add the diced shallot. You will hear a gentle sizzle as it hits the pan. Cook for about 60 seconds, stirring frequently, until the shallot turns translucent and releases a sweet, savoury aroma.

Add the minced garlic and diced jalapeño (if using) to the pan. Stir them through the shallot for about 30 seconds—the garlic will become fragrant and the jalapeño will soften slightly. The kitchen will now smell wonderfully aromatic.

Sprinkle the flour over the vegetables and stir constantly for one minute. This raw flour smell will shift to a nutty, toasted scent, and the mixture will look like a thick paste clinging to the shallots.

Slowly pour in the milk while whisking continuously. The mixture will seize up at first, then loosen into a smooth, pale sauce as you keep whisking. Bring it to a gentle simmer—small bubbles will appear around the edges of the pan, but do not let it boil fiercely.

Reduce the heat to low. Add the single cream and stir until the sauce is uniform and has a slightly thicker, velvety appearance.

Add the grated cheeses by the handful, stirring in one direction with a wooden spoon after each addition. The cheese will melt into the warm liquid, creating a glossy, thick sauce that stretches slightly when lifted with the spoon. The colour will deepen to a rich, creamy orange.

Stir in the cumin, smoked paprika, and salt. Taste the dip—it should be well-seasoned and deeply cheesy. Finish by stirring in the fresh lime juice, which brightens all the flavours. The final texture should be smooth, pourable, and completely uniform without any streaks.

Transfer the queso to a serving bowl, sprinkle the chopped coriander on top, and serve immediately while it is still warm and wonderfully fluid.