Preheat the oven to 400°F. Spread the bacon strips out across a foil-lined baking sheet and place them in a cold oven. Place the bacon on the middle rack and cook for about 10 minutes. Remove from the oven and transfer to a paper towel lined plate.
Blanch the Green Beans
While the bacon is roasting, bring a large pot of water to a boil. Add green beans and salt to the boiling water. Cook the beans until bright green and crisp-tender, about 3 minutes.
Fill a large bowl with ice water while the beans are cooking. Set it next to the sink. Use tongs to transfer the beans to the ice water to stop cooking. (You can also drain beans in a colander and plunge them immediately into ice water.) Once cooled, drain the beans in a colander.
Make the Green Bean Bundles
Pat the green beans dry with a paper towel before tossing them with the oil, garlic, salt, and pepper. Then wrap four beans in each half piece of bacon. Place the wrapped bundles on the same baking sheet used for the bacon.
Combine the butter, brown sugar, and cayenne in a small bowl and warm in the microwave for 30 seconds to melt the butter. Stir to combine and then brush the bacon wrapped beans with the sugar mixture.
Roast for 10-12 minutes, until the green beans are lightly browned and the bacon is crisp.
Notes
Make Ahead Directions: Prep everything up to roasting the bundles and place the wrapped green beans in the fridge for up to 24 hours. When ready to bake, brush with the brown sugar mixture and place on a sheet pan. Roast as directed above.