Cook the bacon in a large saute pan over medium-low heat until the fat is rendered and the bacon is crispy, about 5 minutes. Add the garlic and shallots and sweat for 1 minute. Add the peas and increase the heat to medium. Pour in the orange juice and cook until the peas are tender, about 2 minutes.
Remove from the heat and fold in the orange zest, parsley and butter. Taste for seasoning and add salt if necessary, though you shouldn't need much because the bacon adds a natural saltiness to the dish.