Set the cream cheese out on the counter to come to room temperature. Cold cream cheese will leave lumps you cannot whisk out later.
Preheat the oven to 350°F.
Combine the crust ingredients in a food processor and pulse until the mixture holds together when pressed.
Press the mixture into a parchment lined 9 inch springform pan, working it up the sides. Refrigerate to set while you make the filling.
Fill a shallow baking pan halfway with water and set it on the oven lower rack. This is what keeps the top from cracking.
Combine the cream cheese, yogurt, erythritol, vanilla, lemon juice and 1/4 cup almond flour in the food processor. Blend until completely smooth, scraping the sides once.
Remove the crust from the refrigerator and pour the filling in, smoothing the top.
Place the cheesecake on the middle rack, directly above the water pan.
Bake 30 minutes. Do not open the oven door during baking.
Turn the oven off and leave the cheesecake inside, door closed, for 5 more minutes.
Remove from the oven and cool on the counter for 20 minutes.
Refrigerate overnight to set fully. Do not skip this. A cheesecake cut warm will not hold a slice.
Run a thin knife around the edge, release the springform, slice into 12 and serve.