Cereal bars may feel like a fad of the 90s health-food aisle, but long before foil wrappers and supermarket shelves, Northern China had its own version. In provinces such as Shanxi, where hardy grains, nuts and seeds are among the few crops that truly thrive, these ingredients have sustained people for centuries. They are food with purpose: dense, nourishing and sustaining.

Across China there is an entire category of confections known as sutang (酥糖) — brittle, nut-and-seed sweets made from sesame, peanuts, sunflower seeds, or puffed grains such as millet, rice and wheat. Today you’ll find shops devoted entirely to these crisp delights, stacked high in slabs and shards. But their origins are rural and practical. After a good harvest, farmers would dry their seeds, puff their grains, and bind them with maltose or syrup — a way of preserving abundance for leaner months. Over time, these humble mixtures became celebratory too, offered at Lunar New Year, weddings and temple fairs, where sweetness signalled good fortune.

In Shanxi, I found them sold at the roadside: neat rectangles wrapped in paper, each one a different shade and texture. The version I returned to again and again was flecked with glossy green pumpkin seeds and mixed with puffed millet — earthy, nutty, and just sweet enough. This recipe is my homage to that bar.

Puffing grains is something of a spectacle. In Shanxi, fine river sand is heated in large woks until fiercely hot — the sand holding and distributing the heat evenly. Grains are stirred through and, in an instant, they bloom. It is dramatic and rather beautiful. It is also, in a home kitchen, slightly chaotic. I have tried it myself; the results are unpredictable, and extracting every last grain of sand requires patience. Unless you feel like an afternoon of experimentation, I suggest buying ready-puffed grains.

You may not realise you’ve definitely eaten puffed grains before. Puffed rice appears as Rice Krispies, puffed wheat as Sugar Puffs in the cereal aisle. The Chinese versions, however, are simpler - unseasoned, less processed - allowing the true, toasty flavour of the grain to come through.

Bound with syrup and folded with seeds, they create something deeply satisfying: the snap of brittle, the chew of maltose, the gentle saltiness of seeds against a steady sweetness.

Makes about 12 bars