In a blender, puree the tomatoes with their juices until smooth, about 1 minute; transfer to a medium bowl and set aside.

Add the cashews and ¾ cup water to the blender, then puree until smooth, about 1 minute; set aside if pressure cooking or cover and refrigerate if slow cooking.

In a large bowl, whisk together the garam masala, cumin, ginger and 2 teaspoons salt. Add the chicken and toss to coat; set aside.

On a 6-quart Instant Pot, select More/High Sauté. Add the butter and let melt. Add the onion and cook, stirring occasionally, until softened, 3 to 5 minutes. Add the garlic and cook, stirring, until fragrant, about 30 seconds. Stir in the chicken and tomatoes, then distribute in an even layer.

Press Cancel, lock the lid in place and move the pressure valve to Sealing. Select Pressure Cook or Manual; make sure the pressure level is set to High. Set the cooking time for 10 minutes.

When pressure cooking is complete, quick-release the steam by moving the pressure valve to Venting. Press Cancel, then carefully open the pot.

Stir the cashew puree into the chicken mixture, scraping the bottom of the pot. Select Less/Low Sauté and cook, stirring often, until the sauce has thickened and coats the chicken, 4 to 5 minutes.

Using potholders, carefully remove the insert from the housing and let cool for about 5 minutes. Stir in 3 tablespoons of cilantro, the lime juice and honey, then taste and season with salt and pepper.

Serve sprinkled with the remaining 1 tablespoon cilantro.