Make the crust:

In a medium bowl, mix together crumbs and sugar. then add melted butter and mix until combined and crumbs are moistened. Press the mixture very tightly onto the bottom of a parchment-lined 9-inch springform pan using either your fingers or the bottom of a cup to form a crust layer. Refrigerate until needed.

Make the filling:

Place ¼ cup water in a small bowl and sprinkle gelatin over the surface in a single layer. Be sure not to pile it as that will prevent the crystals from dissolving properly. Let stand for 5-10 minutes to soften.

In a medium bowl, whisk together the powdered sugar and spirulina powder until well combined. In a large mixing bowl and mixer fitted with the paddle attachment, beat the cream cheese until smooth and creamy. Slowly add in the powdered sugar mixture to the cream cheese until smooth and creamy. Add in vanilla extract, lemon zest and juice, beat until combined. Microwave gelatin for 5-10 seconds, just until melted and syrupy. Add gelatin to the cheesecake batter and mix until combined. Set aside.

In another bowl of an electric stand mixer fitted with the whisk attachment, whisk heavy cream until soft peaks form (they should hold their shape but have a soft texture). Using a spatula, gently fold half of the whipped cream into the cream cheese mixture, then fold in the other half.

Pour filling into the springform pan and smooth the top. Cover pan with plastic wrap and place in the fridge for at least 4 hours, or until completely set, before serving. Cheesecake can be left in the fridge for up to 2-3 days. Serve cold.

Cheesecake can also be frozen, wrapped tight, for a month. To thaw, place overnight in the fridge.

Top with berry sauce, fresh fruit, whipped cream, or a rosemary wreath garnish. I sprinkled the top of my cheesecake with more spirulina powder for contrast and to achieve a rich, green color.