Make the Peanut Chutney Powder:
Heat dry skillet or pan over medium heat
Add raw peanuts and dry roast, stirring frequently, for 3-4 minutes until fragrant and lightly golden
Transfer roasted peanuts to a plate
In same dry pan, add cumin seeds, coriander seeds, whole garlic cloves (with skin), and dried red chilies
Dry roast over medium heat, stirring constantly, for 2-3 minutes until aromatic
Garlic should soften and develop dark spots; chilies should darken slightly
Remove from heat and let cool for few minutes
Peel roasted garlic cloves once cool enough to handle
Transfer all roasted ingredients to spice grinder, coffee grinder, or small food processor
Grind to fine powder with no large chunks remaining
Set aside peanut chutney powder
Prepare the Cucumbers:
Wash cucumbers and peel if using regular cucumbers with thick skin (English or Persian can be left unpeeled)
Slice cucumbers thinly (about 1/8 inch thick) using sharp knife or mandoline
Arrange cucumber slices on plate or cutting board
Sprinkle generously with chaat masala to season every slice
Set aside
Make the Yogurt Spread:
In medium bowl, combine 1 cup Greek yogurt
Add 2 tablespoons peanut chutney powder and stir thoroughly
Taste and add more chutney powder if desired for stronger flavor
Add 3/4 teaspoon salt and mix well
Add 2-3 tablespoons chopped fresh cilantro
Stir everything together until well combined
Taste and adjust seasoning if needed
Assemble the Sandwiches:
If desired, trim crusts off bread slices using sharp serrated knife
Spread generous layer of peanut chutney yogurt mixture on one slice of bread
Arrange chaat masala-seasoned cucumber slices on top of spread, overlapping slightly to cover entire surface
Spread another layer of yogurt mixture on second slice of bread
Place second slice spread-side down on top of cucumbers
Press down gently to help everything adhere
Cut sandwich in half diagonally, into triangles, or into finger sandwiches
Repeat with remaining ingredients
Serve:
Arrange sandwiches on serving platter
Garnish with extra cilantro leaves if desired
Serve fresh within 1-2 hours of assembly
Storage Tips:
Peanut chutney powder stores in airtight container at room temperature for up to 1 month
Yogurt spread keeps refrigerated for up to 3 days
Assemble sandwiches just before serving for best texture