If using fresh green beans, slice them thinly into French-style cuts. Place them in a small pot with boiling, lightly salted water. Cover and cook until they reach a crisp-tender texture. For frozen beans, simply prepare according to the package instructions. Once cooked, drain thoroughly and set aside.
In a small skillet, melt the butter over low heat. Add the slivered almonds and cook gently, stirring intermittently, until the almonds turn golden brown and release a nutty aroma. Remove the skillet from the heat and stir in the lemon juice.
Drizzle the almond-butter mixture evenly over the prepared green beans. Serve warm as a simple yet elegant side dish.