The fragrant beans in the Hui oil fragrance in Sister Ma’s gourmet life are fragrant alfalfa. Alfalfa (sweet bean) is an annual herbaceous plant of the Leguminosae family. The whole plant has a fragrant aroma. The flowering period is from April to June and the fruiting period is from July to August. Tonka bean is a traditional seasoning commonly used by Hui people in the northwest when making noodles. It has a special fragrance and is only produced in the northwest region of China. The roasted tonka pea leaves and fruits are greener in color and more fragrant, and are then ground into powder for use. In the past, everyone in the northwest would steam rolls and bake steamed buns. The special fragrance of sweet beans made these ordinary pasta full of surprises.