Sautéed cucumbers are lightly vegetal, similar to zucchini and take on the flavor well of whatever sauce they are braised in. Here, it is a creamy tarragon sauce with French flair but can be adapted for whatever cuisine you prefer. For example, a bit of ginger, garlic, and coconut milk would make an excellent Asian twist. A pinch of Garam Masala and coconut milk would produce and Indian influenced dish. Jalapeño and cumin with cilantro would push this more in a Latin American direction.
Add the butter, cucumbers, and salt to a medium pan and heat over medium high heat. Cook, stirring occasionally until the cucumbers are tender, about 5-10 minutes. Add the cream and mustard and reduce to desired consistency. I like to reduce to a couple of tablespoons of liquid, about 3-5 minutes more. Off heat, add the tarragon. Season with a bit more salt, if desired.