Preheat oven to 350°. Roast almonds in a shallow pan until golden, stirring once, 8 to 10 minutes.
Meanwhile, bring 2 1/2 cups water and 1/2 tsp. salt to a boil in a medium saucepan. Add the freekeh, garlic, and chile flakes. Cover, reduce heat, and simmer until freekeh is tender, 20 to 25 minutes. Let stand 5 minutes. Strain freekeh, then spread on a rimmed baking sheet to cool (put it in the fridge if you're in a hurry). Discard large pieces of garlic.
While freekeh cooks, cut ribs and stems from collards; save them for another use. Rinse leaves and spin dry. Stack a few at a time, roll lengthwise into a long cigar, and very thinly slice crosswise. In a large bowl, toss collards well with 3/4 tsp. salt.
Add 2 tbsp. vinegar, the oil, and pepper to collards and toss to blend. Add cooled freekeh and toss to combine; then add almonds, pear, and green onions and toss gently. Season to taste with more vinegar and salt if you like.
*Find cracked freekeh at well-stocked grocery stores and natural-foods stores, and at bobsredmill.com.