Preheat oven to 350°. Line a rimmed baking sheet with parchment paper.
Using a 1¾-inch round cutter, cut 8 circles from frozen bread. Place on prepared baking sheet. Brush tops of bread rounds with melted butter.
Bake until crisp, 7 to 8 minutes. Let cool.
Increase oven temperature to 450°. Line another rimmed baking sheet with foil. Lightly spray foil with cooking spray.
Using a sharp knife, trim bottom of artichoke hearts to level. Trim top of artichoke hearts, if needed. Set artichoke hearts on prepared baking sheet.
Using a sharp knife, cut each bacon slice in half lengthwise to create a total of 8 thin strips. Wrap each artichoke heart with a bacon strip, overlapping as needed. Secure bacon with a wooden pick.
Bake until bacon is browned and crisp, 18 to 20 minutes.
Top each toast round with a kale leaf and a baked artichoke heart, carefully removing toothpicks. Fill artichoke hearts with a dollop of mustard. Sprinkle with cheese. Serve warm.
Recipe by TeaTime Magazine at https://teatimemagazine.com/bacon-artichoke-canapes/