Follow these steps carefully for a perfectly set and smooth Vanilla Panna Cotta:

1. Bloom the Gelatin: Pour the 3 tablespoons of cold water into a small, shallow bowl. Sprinkle the powdered gelatin evenly over the surface of the water. Do not stir immediately; let it sit undisturbed for 5-10 minutes. The gelatin will absorb the water and become thick and jelly-like. This process, known as blooming, ensures the gelatin dissolves smoothly without clumps.
2. Prepare the Vanilla: If using a vanilla bean, place it on a cutting board. Using the tip of a sharp knife, split the bean lengthwise from end to end. Use the back (dull side) of the knife to scrape out the tiny black seeds from inside both halves. Set the seeds and the pod aside. If using vanilla extract, simply measure it out and set it aside to be added later.
3. Heat the Cream Mixture: In a medium saucepan, combine the heavy cream, whole milk, granulated sugar, and the pinch of salt. If using a vanilla bean, add both the scraped seeds and the split pod to the saucepan.
4. Warm Gently: Place the saucepan over medium-low heat. Heat the mixture gently, stirring occasionally with a whisk or wooden spoon to dissolve the sugar completely. It’s crucial not to boil the mixture. Bring it only to a gentle simmer – you should see small bubbles forming around the edges of the pan, and steam rising. Boiling can affect the cream’s texture and potentially scald it.
5. Remove from Heat & Steep (if using vanilla bean): Once the mixture reaches a gentle simmer and the sugar is dissolved, remove the saucepan from the heat. If you used a vanilla bean, cover the saucepan and let the mixture steep for about 15-20 minutes. This allows the vanilla pod to fully infuse its flavour into the cream mixture. If you are using vanilla extract, skip this steeping step.
6. Dissolve the Bloomed Gelatin: After steeping (or immediately after removing from heat if not steeping), gently reheat the cream mixture over low heat for a minute or two if it has cooled down significantly. It needs to be warm enough to dissolve the gelatin, but again, avoid boiling. Add the bloomed gelatin mixture to the warm cream. Whisk continuously until the gelatin is completely dissolved and no granules remain. This usually takes about 1-2 minutes. Ensure thorough mixing.
7. Add Vanilla Extract (if using): If you are using vanilla extract instead of a bean, stir it into the mixture now, after the gelatin has been dissolved and the pan is off the heat.
8. Strain the Mixture: Position a fine-mesh sieve over a large bowl or a pitcher with a spout (a pitcher makes pouring into molds easier). If you used a vanilla bean, remove the pod from the cream mixture first. Carefully pour the warm panna cotta mixture through the sieve. This crucial step removes the vanilla pod (if used) and any potential small clumps of undissolved gelatin or milk solids, ensuring a perfectly smooth and silky final texture.
9. Prepare the Molds: Lightly grease your chosen molds (ramekins, small bowls, glasses, or silicone molds) with a neutral-flavoured oil or cooking spray, wiping out any excess with a paper towel. This light greasing aids in unmolding later, though it’s optional if you plan to serve the panna cotta directly in its container. For 6 servings, standard 4-6 ounce ramekins work well.
10. Pour into Molds: Carefully divide the strained panna cotta mixture evenly among the prepared molds. Pouring from a pitcher makes this process neater.
11. Chill to Set: Cover the molds loosely with plastic wrap (press it gently onto the surface if you want to prevent a skin from forming, though this isn’t strictly necessary). Carefully transfer the molds to the refrigerator. Chill for at least 4-6 hours, or preferably overnight, until the panna cotta is completely firm and set. It should have a gentle wobble when shaken lightly but hold its shape. Insufficient chilling time is a common reason for panna cotta not setting properly.
12. Unmold (Optional): If you wish to unmold the panna cotta, fill a bowl with warm (not hot) water. Dip the bottom of one mold into the warm water for just 5-10 seconds – be careful not to let water get into the panna cotta. Loosen the edges gently with your fingertip or the tip of a thin knife. Place a dessert plate over the top of the mold, invert it quickly and confidently, and give it a gentle shake. The panna cotta should release onto the plate. If it doesn’t release easily, repeat the brief warm water dip. Repeat for the remaining molds.
13. Serve: Serve the panna cotta chilled, either in its mold or unmolded onto plates. Garnish as desired (see “How to Serve” section below).