Process almonds, about 1/4 at a time, with
on/off pulses in electric spice grinder to fine powder. Dip chicken
into almonds on small plate to coat all sides; reserve remaining almonds.
Heat 1 tablespoon oil and the butter in deep 10-inch skillet
over medium heat until foam subsides. Add as many breasts as will
fit in single layer without crowding. Cook until chicken is light
brown on both sides, about 3 minutes per side, reducing heat if
almonds get too dark; remove to plate.
Repeat with remaining chicken,
adding 1 tablespoon oil, if needed.
Add remaining 1 tablespoon
oil and the onion to skillet; sauté over medium heat until soft,
about 3 minutes.
Add chile, chopped tomato and garlic; sauté 1 minute.
Add stock, salt and reserved almonds; heat over high heat to boiling.
Add chicken to skillet; reduce heat to low. Simmer, covered, until
chicken is cooked through, 15 to 20 minutes.
Remove chicken to serving
dish; keep warm, covered.
Add cream to cooking liquid; heat
over medium-high heat to boiling. Cook and stir until sauce is slightly
thickened, 3 to 5 minutes; pour over chicken.