Heat oven to 325 degrees. Spray a heatproof glass loaf pan (8 1/2-by-4 1/2-by-2 1/2) with vegetable oil spray, line bottom and sides with parchment paper, and set aside.
In a medium saucepan over medium heat, melt butter. Add flour, and stir to combine. Cook until a paste forms, making sure mixture does not brown, about 5 minutes.
In a medium bowl, combine cream and milk. Add to flour mixture, whisking constantly. Bring to a boil; add cheese and salt. Return mixture to a boil, whisking often.
In a large bowl, whisk together egg yolks and whole egg. Remove pan from heat and whisk milk mixture into egg mixture.
Strain through a fine-mesh sieve into prepared loaf pan. Make sure the liquid does not touch the top of the pan. Cover with parchment paper and foil. Line a pan large enough to hold the loaf pan with a clean kitchen towel. Fill pan with enough hot water to come 3/4 of the way up the sides of the loaf pan. Transfer to oven and bake for 1 1/2 to 2 hours. The pudding should still jiggle in the middle (the edges may be slightly rounded but not "souffleed").
Remove from water bath and let cool to room temperature. Refrigerate overnight.
Heat oven to 350 degrees. To serve, unmold the pudding onto a cutting board. Cut into 6 to 8 slices and place each slice on an ovenproof plate. Bake until the pudding is just warm, about 2 to 3 minutes. Pour pea sauce around pudding and garnish with pea shoots.