In a large saute pan over medium-high heat, add the butter. Cook the butter until browned and nutty, about 1 to 2 minutes. Add the almonds and toast, tossing frequently for about 1 minute. Stir in the garlic and jalapeno, then add the green beans and toss until warmed through. Season the beans with salt and pepper, to taste, and a dash of fresh lemon juice. Transfer to a serving dish and serve.