Step 1: Prepare the Gluten-Free Crust

1. Preheat and Prep: Position a rack in the middle of your oven and preheat to 350°F (175°C). Lightly grease the bottom and sides of a 9-inch springform pan.

2. Combine Crust Ingredients: If your pecans are not already ground, pulse them in a food processor until they form a fine, sandy meal. In a medium bowl, combine the almond flour, ground pecans, sugar, and salt. Whisk to combine.

3. Add Butter: Pour the melted butter over the dry ingredients and stir with a fork until the mixture is evenly moistened and resembles wet sand.

4. Form and Par-Bake the Crust: Press the crumb mixture firmly and evenly into the bottom and about one inch up the sides of the prepared springform pan. Use the flat bottom of a measuring cup to get a tight, even layer. Place the pan on a baking sheet and bake for 10-12 minutes, until the crust is lightly golden and fragrant.

5. Cool the Crust: Remove the pan from the oven and place it on a wire rack to cool completely while you prepare the filling. Reduce the oven temperature to 325°F (160°C).

Step 2: Make the Matcha Cheesecake Filling

1. Beat the Cream Cheese: In the bowl of a stand mixer fitted with the paddle attachment, or in a large bowl with a hand mixer, beat the room temperature cream cheese on medium-low speed until it is completely smooth and creamy, with no lumps. This should take about 2-3 minutes. Scrape down the sides and bottom of the bowl frequently.

2. Add Sugar and Matcha: Add the granulated sugar and sifted matcha powder to the cream cheese. Continue to beat on low speed until just combined, scraping the bowl again to ensure everything is incorporated. Sifting the matcha is crucial to prevent green clumps in your final product.

3. Incorporate Eggs: With the mixer on low speed, add the room temperature eggs one at a time, mixing until the yolk just disappears before adding the next. Do not overbeat after adding the eggs; this incorporates too much air, which is a primary cause of cheesecake cracking.

4. Add Final Wet Ingredients: In a separate small bowl, whisk together the room temperature sour cream, heavy cream, vanilla extract, and lemon juice. With the mixer still on low speed, slowly pour this mixture into the batter and mix until just combined and the batter is smooth.

5. Final Scrape and Tap: Remove the bowl from the mixer. Use a silicone spatula to give the batter one final, gentle fold from the bottom up to ensure it is uniformly mixed. Tap the bowl on the counter a few times to release any large air bubbles.

Step 3: Assemble and Bake with a Water Bath

1. Prepare the Water Bath: A water bath (bain-marie) is the secret to a creamy, crack-free cheesecake. Tear off two large sheets of heavy-duty aluminum foil. Place the cooled springform pan in the center and carefully wrap the foil up the sides of the pan, creating a watertight seal. This prevents any water from seeping into the crust.

2. Fill the Pan: Pour the matcha cheesecake batter over the cooled crust in the springform pan and spread it into an even layer with your spatula.

3. Set Up the Bath: Place the foil-wrapped pan into a large roasting pan. Bring a kettle or pot of water to a boil. Carefully place the roasting pan onto the oven rack. Pour the hot water into the roasting pan until it comes about one inch up the sides of the springform pan.

4. Bake: Bake at 325°F (160°C) for 65-75 minutes.

Step 4: Cool the Cheesecake Slowly (The Most Important Step)

1. Check for Doneness: The cheesecake is done when the outer edges (about 2-3 inches) are set, but the very center still has a slight wobble or jiggle when you gently nudge the pan. Do not over-bake.

2. Slow Oven Cool: Turn the oven off completely, but do not open the oven door. Let the cheesecake sit in the cooling oven for 1 hour.

3. Counter Cool: After 1 hour, carefully remove the cheesecake from the water bath, unwrap the foil, and place the pan on a wire rack to cool to room temperature, about 2-3 hours.

4. Chill: Once at room temperature, run a thin knife around the edge of the cheesecake to loosen it from the pan (this also helps prevent cracking as it settles). Cover the pan loosely with plastic wrap and transfer it to the refrigerator to chill for at least 6 hours, but preferably overnight. This long chill time is essential for the cheesecake to fully set and for the flavors to meld and deepen.