À la Printanière in classical French cooking terms indicates a side dish of turnips and carrots cooked in a stock, then buttered, along with asparagus tips and green peas.
In the latter half of the 1900s, outside of French haute cuisine, it came to indicate more loosely a side accompaniment of fresh vegetables, particularly those first to appear in a growing season.
Language Notes
Means “in a springtime fashion”, perhaps referring to the last of the stored vegetables and the first of the new crop.