Prepare a large bowl filled with ice water and set aside.
In a deep pan or a pot, fill with water 2/3rds of the way and bring to a boil. Add the green beans and boil for 4-5 minutes or until tender and crisp. Strain and immediately add the green beans to the ice. Allow to cool completely, strain, and pat dry. Set aside.
Using a large pan, bring to medium heat and add the almonds. Rotate and saute for 3-5 minutes or until the almonds are lightly toasted. Set aside and clean out the pan.
Using the same pan, add the bacon and cook until crisp. Set aside and reserve about 2 tbsp of bacon fat in the pan.
To the same pan over medium heat and saute the onion and garlic until the onion is translucent. Add the blanched green beans, salt, pepper, and balsamic vinegar. Stir for 4-5 minutes or until green beans are tender.
Add the green beans to a serving dish and top with almonds, bacon, and lemon zest. Serve with a serving spoon.