As smooth as glass and almost as translucent, this pulled sugar topper captures tender Marcona almonds in midair. A little fleur de sel accentuates the delicate balance between salty and sweet. Save the pralines, if you can, for stylish garnishes.
Lightly coat a nonstick baking mat or a piece of parchment with oil, and place on a heatproof surface. Bring sugar and water to a boil in a small saucepan over medium-high heat, tilting pan to swirl and washing down sides with a wet pastry brush to prevent crystals from forming. Boil, without stirring, until mixture turns pale amber, about 8 minutes.
Remove from heat, and stir in almonds. Pour mixture onto center of prepared surface, and sprinkle with fleur de sel. Let stand just until the edges are cool enough to handle. Working quickly and using gloved hands lightly coated with oil, pull pieces of caramel and almonds away from the center until caramel starts to harden and you are able to pull long, thin pieces before they break away. Transfer to a parchment-lined baking sheet to cool completely. Repeat. (If praline begins to harden, place on a baking sheet in a 375-degree oven until pliable; you can do this only once before the sugar begins to crystallize.)
Pralines can be stored in an airtight container at room temperature for up to 2 weeks.