Preheat oven to 425 degrees F (220 degrees C). Lay a piece of parchment paper or tin foil onto a baking sheet and spray it with Vegetable Oil Cooking Spray (to taste) and set aside.
In a medium bowl, combine Coarse Dijon Mustard (2 tablespoon), Olive Oil (3 tablespoon), Garlic (2 clove), Fresh Rosemary (1 tablespoon), Kosher Salt (1/2 teaspoon), and Ground Black Pepper (1/2 teaspoon). Whisk to combine.
Add the Baby Dutch Potato (1 pound) and toss until potatoes are well coated.
Arrange coated potatoes on the baking sheet, preferably flesh side down. This will promote nice browning and crisping. Roast for 15 minutes.
Sprinkle with Lemon (1/2 teaspoon). Then, using a spatula, flip potatoes and continue cooking for an additional 10-15 minutes, until crispy on the outside and tender on the inside.
Sprinkle with Fresh Parsley (2 teaspoon) and serve.