In a small skillet over medium heat, melt 2 tablespoons of the butter. Add the panko and toast, stirring constantly, for about 2 minutes until golden brown and crisp. Remove from the heat and stir in the lemon zest and a pinch of salt. Set aside.

Fill a large saucepan two-thirds full of water and bring to a boil over high heat. Add 1 tablespoon of salt. Add the beans and cook for about 2 minutes until bright green and still very crisp. Meanwhile, fill a large bowl two-thirds full of ice water. Using tongs or a slotted spoon, immediately transfer the beans to the ice water. Let cool in the water for 2 minutes and then drain thoroughly, blot dry with paper towels, and set aside.

In a 12-inch skillet over medium-high heat, melt the remaining 3 tablespoons butter and swirl to coat the pan. Add the green beans and sauté, stirring constantly, for about 3 minutes until the beans are heated through and crisp-tender. Add the lemon juice and almonds and sauté for 1 minute longer. Season to taste with salt and pepper. Transfer to a warmed serving bowl. Sprinkle with the panko topping and serve immediately.

This sauté is best when made right before serving. However, the green beans can be blanched up to 1 day in advance. Spread the cooled beans on dry paper towels or a clean cotton towel, roll up jelly-roll style, and place in a sealed plastic bag. Remove from the refrigerator 2 hours before sautéing. The panko topping and toasted almonds can be prepared up to 1 day in advance. Cover and store in separate airtight containers at room temperature.