Rosemary and olive oil infusion isn't difficult to make and can quickly add a new dimension to your culinary skills. Use the aromatic blend instead of herbs and spices in meat and vegetable dishes. Drizzle the oil over pasta, use it as a dipping sauce for your favorite crusty Italian bread or as a starter for sauces, marinades and salad dressings. A rosemary and olive oil infusion also can be a gift for the foodies on your list.
Place 2 1/2 cups extra virgin olive oil in a heavy glass, stainless steel or enamel saucepan. Avoid aluminum, which can discolor the oil and impart a metallic taste.
Add 1 cup dried rosemary. If you have fresh rosemary, dry it first, as the moisture in fresh rosemary can cause the oil to spoil quickly. Avoid using any water in the olive oil infusion, as even a small amount of water can harbor bacteria, which can cause botulism. To dry fresh rosemary, place the herbs in the sun or dry the rosemary in a food dehydrator until all moisture is removed.
Place the saucepan on medium heat and heat the oil and rosemary to 140 degrees Fahrenheit. If you don't have a cooking thermometer, heat the mixture until the oil just begins to bubble. Allow the mixture to simmer slowly for five minutes.
Pour the mixture into a mixing bowl and allow it to cool, then add 2 1/2 additional cups extra virgin olive oil. If desired, leave the rosemary in the oil for decoration and flavor, or strain the rosemary and olive oil infusion by pouring it through a fine mesh sieve lined with cheesecloth.
Pour the rosemary and olive oil infusion into a glass bottle. Cap the bottle securely and store the oil in the refrigerator for up to one month.